Bafang Ebike Motor Not Working: Error Code List

Error Code 04: Throttle Has Not Returned to Its Correct Position

Error Code: 04
Cause: The throttle has not returned to its correct position.
Result: The display shows Error Code 04, and the motor may not operate normally.

What Does Bafang Error Code 04 Mean?

Bafang Error Code 04 indicates that the eBike system detects an abnormal throttle position. In most cases, the throttle has not fully returned to its default or zero position.

The throttle is mounted on the handlebar and sends an input signal to the controller. When you press or twist the throttle, the controller uses this signal to determine when and how much power should be delivered to the motor.

The system continuously monitors the throttle after the eBike is turned on. If the throttle remains engaged, becomes physically stuck, or sends an abnormal signal, Error Code 04 may appear on the display.

Common Symptoms

When this problem occurs, you may notice:

• The display shows 04.
• The throttle does not return smoothly to its resting position.
• The throttle may feel stuck or jammed.
• The motor does not respond to the throttle.
• Motor assistance may be disabled as a safety measure.

How to Fix Bafang Error Code 04

Step 1: Check Whether the Throttle Is Stuck

Turn off the eBike and inspect the throttle on the handlebar.

Press or twist the throttle and then release it. It should move freely and immediately return to its normal resting position.

Inspection Result	Solution
The throttle is stuck or does not return correctly.	Replace the throttle.
The throttle moves normally and is not stuck.	The controller may be faulty. Inspect the connections and replace the controller if necessary.

Also check whether the throttle is being obstructed by the grip, brake lever, handlebar accessory, dirt, or physical damage.

Step 2: Clear Error Code 04

After repairing or replacing the faulty component:

1. Reconnect all components securely.
2. Make sure the throttle is completely released.
3. Turn on the eBike system.
4. Check the display again.

Result	Next Action
Error Code 04 is no longer active.	The repair is complete and the eBike should operate normally.
Error Code 04 remains active.	Repeat Step 1 and check the throttle and controller again. If the problem persists, contact a Bafang dealer or qualified eBike technician.

Quick Troubleshooting Summary

Error 04 → Check throttle position → If stuck, replace throttle → If throttle works normally, check controller → Reconnect components → Restart system → Confirm the error has disappeared.

Tip: Always release the throttle completely before turning on the eBike. Holding or pressing the throttle during startup can cause the system to detect an incorrect throttle position.

Error Code 07: Over Voltage Protection

Error Code: 07
Cause: Over voltage protection.
Result: The display shows Error Code 07, and the motor cannot operate.

What Does Bafang Error Code 07 Mean?

Bafang Error Code 07 means that the eBike system has detected a voltage that is too high and has activated its over-voltage protection.

The battery is the main power source for the eBike, supplying electrical energy to the motor and other components. Its location varies depending on the eBike model and frame design.

Once the system is turned on, it continuously monitors battery voltage. If the detected voltage exceeds the acceptable range, Error Code 07 appears and the motor is disabled to protect the electrical system.

Common Symptoms

When Error Code 07 occurs, you may notice:

• The display shows 07.
• The motor does not work.
• Pedal assistance may be unavailable.
• Throttle operation, if equipped, may be disabled.
• The battery may appear charged, but the eBike still provides no motor assistance.

How to Fix Bafang Error Code 07

Step 1: Check the Battery Voltage with the BESST Tool

Connect the eBike to the Bafang BESST diagnostic tool and read the system voltage.

Check whether the reported battery voltage is within the correct operating range for your particular Bafang system.

An abnormally high voltage reading may indicate a battery, BMS, controller, or compatibility problem.

Important: Do not replace the battery with a higher-voltage battery unless the Bafang motor, controller, display, and other electrical components are specifically designed to support that voltage.

Step 2: Update the Controller

Use the Bafang BESST tool to update the controller according to the manufacturer's diagnostic procedure.

Result	Solution
The system returns to normal after the controller update.	Go to Step 3 and confirm that the error has cleared.
The system does not return to normal after the controller update.	Replace or professionally test the battery.

Because BESST is primarily a professional diagnostic/service tool, riders who do not have access to it should have this step performed by a Bafang dealer or qualified eBike technician.

Step 3: Clear Error Code 07

After completing the diagnosis or repair:

1. Connect all components correctly.
2. Make sure the battery is properly installed.
3. Turn on the eBike system.
4. Check the display.

Result	Next Action
Error Code 07 is inactive.	The repair is complete.
Error Code 07 is still active.	Return to Step 1 and repeat the diagnostic procedure. If all steps have been completed and the error remains, contact Bafang or an authorized service provider.

Quick Troubleshooting Summary

Error 07 → Check battery/system voltage with BESST → Update the controller → If the system still does not return to normal, test or replace the battery → Reconnect all components → Restart the eBike → Confirm Error 07 has cleared.

Safety Note: An over-voltage fault involves the eBike's high-current battery system. Do not open, modify, or attempt internal repairs on a lithium-ion battery pack. If the battery voltage or BMS appears abnormal, have the battery inspected by a qualified technician.

Error Code 08: Hall Sensor Error

Error Code: 08
Cause: Error with the Hall sensor.
Result: The display shows Error Code 08, and the motor may not operate correctly.

What Does Bafang Error Code 08 Mean?

Bafang Error Code 08 indicates a problem with the motor's Hall sensor system.

Hall sensors act as electronic switches that detect the position of the motor's rotor. This information allows the controller to energize the motor phases at the correct time, helping the motor run smoothly and continuously.

The Hall sensors are installed on the motor stator. After the eBike system is switched on, the diagnostic system continuously checks for Hall sensor-related faults.

If an abnormal Hall sensor signal or related connection problem is detected, Error Code 08 appears on the display.

Common Symptoms

Depending on the motor and the type of failure, you may notice:

• The display shows 08.
• The motor does not run.
• Motor assistance cuts in and out.
• The motor runs roughly or inconsistently.
• The motor may make unusual noises or vibrations.
• Pedal assist or throttle response may stop working.

How to Fix Bafang Error Code 08

Step 1: Check the Motor Cable and Connectors

For applicable front-motor (FM) and rear-motor (RM) systems, inspect all cables and connectors coming from the motor.

Look carefully for:

• Loose connectors
• Corroded connector pins
• Bent pins
• Broken pins
• Dirt or debris inside the connector
• Damaged wire insulation
• Broken connector shells
• Other visible cable or wiring damage

Disconnect the motor connector with the eBike powered off and inspect the pins carefully. When reconnecting it, make sure the connector is fully seated and correctly aligned.

Inspection Result	Solution
A damaged or contaminated connection is found.	Clean the connector and pins. Repair the damaged wiring, connector, or pins if possible.
All motor cables and connectors are correctly connected and no external damage is found, but Error 08 remains.	The fault may be inside the motor. Replace or professionally inspect the motor.

Important: Do not force a motor connector together. Bent or damaged pins can create additional communication or Hall sensor problems.

Step 2: Clear Error Code 08

After checking or repairing the motor connection:

1. Reconnect all components.
2. Make sure all motor connectors are properly seated.
3. Turn on the eBike system.
4. Check the display for Error Code 08.

Result	Next Action
Error Code 08 is inactive.	The repair is complete.
Error Code 08 is still active.	Return to Step 1 and inspect the motor wiring again. If everything has been checked and the error remains, contact Bafang or a qualified eBike technician.

What If the Wiring Looks Fine?

If the external motor cable and connectors are in good condition but Error Code 08 keeps returning, the Hall sensor or another internal motor component may be faulty.

Because the Hall sensors are located inside the motor, diagnosing or replacing them generally requires motor disassembly and electrical testing. For most riders, professional motor inspection or replacement is the safer option.

Quick Troubleshooting Summary

Error 08 → Turn off the eBike → Check motor cable and connectors → Look for loose, dirty, corroded, bent, or broken connections → Clean or repair damaged connections → Restart the system → If Error 08 remains despite correct connections, inspect or replace the motor.

Error Code 09: Motor Phase Winding Fault

Error Code: 09
Cause: Fault with the motor phase winding.
Result: The display shows Error Code 09, and the motor cannot operate.

What Does Bafang Error Code 09 Mean?

Bafang Error Code 09 indicates that the system has detected a fault with one or more of the motor's phase windings.

Bafang eBike motors use a three-phase motor design. All three phases must operate correctly for the motor to generate smooth and reliable power. If the system detects an abnormality in a phase winding, it may disable the motor and display Error Code 09.

The phase windings are located inside the motor, so this error generally indicates an internal motor problem rather than a simple display or external sensor fault.

Common Symptoms

When Error Code 09 occurs, you may experience:

• The display shows 09.
• The motor does not work.
• Pedal assistance is unavailable.
• The throttle, if equipped, does not drive the motor.
• The motor may have stopped working suddenly before the error appeared.
• Restarting the eBike does not permanently clear the error.

How to Fix Bafang Error Code 09

Step 1: Replace or Professionally Inspect the Motor

According to Bafang's troubleshooting procedure, the recommended action for Error Code 09 is to replace the motor.

Because the three-phase windings are located inside the motor, diagnosing the fault usually requires specialized electrical testing and, in some cases, motor disassembly.

For most eBike owners, internal motor repair is not recommended. Have the motor inspected by a Bafang dealer or qualified eBike technician if you want to confirm the diagnosis before replacing it.

Diagnosis	Solution
Error Code 09 indicates a motor phase winding fault.	Replace the motor.
You are unsure whether the motor itself is defective.	Have the motor and related electrical system professionally diagnosed before replacement.

Note: Simply restarting the display or removing and reinstalling the battery is unlikely to solve a genuine motor phase winding fault.

Step 2: Clear Error Code 09

After the motor has been replaced or repaired:

1. Connect all components correctly.
2. Check that the motor connectors are fully seated.
3. Turn on the eBike system.
4. Check whether Error Code 09 appears again.

Result	Next Action
Error Code 09 is inactive.	The repair is complete.
Error Code 09 is still active.	Return to Step 1 and recheck the repair and connections. If all steps have been completed and the error remains, contact Bafang or an authorized service provider.

Can You Ride an eBike with Error Code 09?

Generally, no. When Error Code 09 is active, the motor cannot operate normally and electric assistance is disabled. Continuing to repeatedly power-cycle or attempt to run a motor with an internal phase fault will not address the underlying problem.

You may still be able to pedal the bicycle manually if there are no other mechanical problems, but the electric drive system should be inspected before further powered use.

Quick Troubleshooting Summary

Error 09 → Motor phase winding fault detected → Motor cannot work → Replace or professionally inspect the motor → Reconnect all components → Restart the system → Confirm Error Code 09 has cleared.

Error Code 10: Motor Over-Temperature

Error Code: 10
Cause: The temperature inside the motor has reached its maximum protection limit.
Result: The display shows Error Code 10, and the motor cannot operate.

What Does Bafang Error Code 10 Mean?

Bafang Error Code 10 indicates that the motor has become too hot and the system's thermal protection has been activated.

A temperature sensor installed inside the motor continuously monitors its internal temperature while the eBike system is running. If the temperature reaches the maximum protection threshold, the system disables the motor to help prevent overheating damage.

In many cases, Error Code 10 is temporary and disappears after the motor has had enough time to cool down.

What Can Cause a Bafang Motor to Overheat?

Motor overheating can occur when the eBike is placed under sustained heavy load. Common contributing factors include:

• Climbing long or steep hills
• Riding at high power for extended periods
• Carrying a heavy rider or cargo
• Frequent acceleration under heavy load
• Riding in very hot weather
• Using too high a gear when climbing
• Operating the motor at low speed under high load for extended periods

If Error Code 10 appears frequently during normal riding conditions, however, the motor or its internal temperature sensing system may require inspection.

Common Symptoms

When Error Code 10 occurs, you may notice:

• The display shows 10.
• The motor suddenly stops providing assistance.
• Pedal assist no longer works.
• The throttle, if equipped, does not power the motor.
• The motor housing may feel unusually warm or hot.
• The eBike may begin working normally again after cooling down.

How to Fix Bafang Error Code 10

Step 1: Turn Off the eBike and Let the Motor Cool Down

Stop riding and turn off the eBike system.

Allow the motor and eBike to cool naturally before turning the system back on. Avoid repeatedly restarting the motor while it is still hot.

If possible, move the bike to a shaded, well-ventilated location while waiting.

Result	Solution
The system returns to normal after cooling down.	Proceed to Step 2 and confirm that Error Code 10 has cleared.
The system does not return to normal after the motor has fully cooled down.	The motor or internal temperature sensor may be faulty. Replace or professionally inspect the motor.

Important: Do not try to cool an overheated motor rapidly by pouring cold water over it. Allow it to cool naturally.

Step 2: Clear Error Code 10

Once the motor has cooled:

1. Make sure all components are properly connected.
2. Turn on the eBike system.
3. Check the display.
4. Test the motor at low load if the error has disappeared.

Result	Next Action
Error Code 10 is inactive.	The system has returned to normal and the repair/check is complete.
Error Code 10 remains active.	Return to Step 1. If the motor is completely cool and the error remains, contact Bafang or a qualified eBike technician.

What If Error Code 10 Keeps Coming Back?

An occasional Error Code 10 after an unusually demanding ride may simply mean the motor reached its thermal protection limit.

However, repeated overheating during ordinary riding should be investigated. It may indicate excessive motor load, an internal motor problem, or a fault with the temperature sensing system.

To reduce the chance of overheating, use lower mechanical gears when climbing, avoid prolonged high-load operation at very low speeds, reduce unnecessary cargo where possible, and give the motor time to cool during demanding rides.

Quick Troubleshooting Summary

Error 10 → Stop riding → Turn off the eBike → Allow the motor to cool naturally → Restart the system → If Error 10 disappears, normal operation can resume → If Error 10 remains after the motor has fully cooled, inspect or replace the motor.

Error Code 11: Motor Temperature Sensor Fault

Error Code: 11
Cause: Motor temperature sensor fault.
Result: The display shows Error Code 11, and the motor cannot operate.

What Does Bafang Error Code 11 Mean?

Bafang Error Code 11 indicates a fault with the motor's internal temperature sensor.

The motor temperature sensor measures the temperature inside the motor and helps protect it against overheating. The eBike system continuously monitors this sensor after the system is switched on.

If the controller cannot receive a valid temperature signal from the sensor, Error Code 11 appears and the motor is disabled.

Unlike Error Code 10, which indicates that the motor has actually reached its maximum temperature protection limit, Error Code 11 indicates a problem with the temperature sensor itself or its associated internal circuitry.

Common Symptoms

When Error Code 11 occurs, you may notice:

• The display shows 11.
• The motor does not provide assistance.
• Pedal assist stops working.
• The throttle, if equipped, cannot drive the motor.
• The error may appear immediately after the eBike is turned on.
• Allowing the motor to cool down does not clear the error.

How to Fix Bafang Error Code 11

Step 1: Replace the Motor

According to Bafang's troubleshooting procedure, the recommended solution for Error Code 11 is to replace the motor.

The temperature sensor is installed inside the motor. Therefore, it is generally not treated as an external, user-serviceable component.

Diagnosis	Solution
Error Code 11 is displayed and the motor cannot operate.	Replace the motor.
You want to confirm the fault before replacing the motor.	Have the motor professionally diagnosed by a Bafang dealer or qualified eBike technician.

Because this error involves an internal motor component, simply restarting the eBike or allowing the motor to cool down will generally not fix a genuine Error Code 11.

Important: Do not confuse Error Code 11 with Error Code 10. Code 10 means the motor is too hot; Code 11 means the motor temperature sensor has a fault.

Step 2: Clear Error Code 11

After the motor has been replaced:

1. Connect all components correctly.
2. Check that the motor cables and connectors are securely installed.
3. Turn on the eBike system.
4. Check whether Error Code 11 is still displayed.

Result	Next Action
Error Code 11 is inactive.	The repair is complete.
Error Code 11 is still active.	Return to Step 1 and recheck the motor installation and connections. If all steps have been completed and the error remains, contact Bafang or an authorized service provider.

Error Code 10 vs. Error Code 11

These two Bafang error codes are related to motor temperature but indicate different problems:

Error Code	Meaning	Typical Solution
10	Motor temperature has reached the maximum protection value.	Turn off the system and allow the motor to cool.
11	Motor temperature sensor fault.	Replace or professionally inspect the motor.

This distinction is important because waiting for the motor to cool can solve Error 10, while it normally will not solve Error 11.

Quick Troubleshooting Summary

Error 11 → Motor temperature sensor fault detected → Motor cannot operate → Replace or professionally inspect the motor → Reconnect all components → Turn on the system → Confirm that Error Code 11 has cleared.

Error Code 12: Motor Over-Current / Controller Current Sensor Fault

Error Code: 12
Cause: Controller current sensor fault / motor over-current protection fault.
Result: The display shows Error Code 12, and the motor cannot operate.

What Does Bafang Error Code 12 Mean?

Bafang Error Code 12 indicates a problem with the controller's current sensing system.

The controller contains a current sensor that monitors the electrical current being supplied to the motor. This sensor is an important part of the eBike's over-current protection system. If the controller detects an abnormal current-sensor signal, it may shut down motor assistance and display Error Code 12.

The current sensor is located inside the controller, which means this fault generally cannot be corrected by adjusting an external sensor or cable.

Common Symptoms

When Error Code 12 occurs, you may notice:

• The display shows 12.
• The motor does not work.
• Pedal assistance is unavailable.
• The throttle, if equipped, does not drive the motor.
• The error may return immediately after restarting the eBike.
• Turning the system off and on may not permanently clear the fault.

How to Fix Bafang Error Code 12

Step 1: Replace the Controller

According to Bafang's troubleshooting procedure, the recommended solution for Error Code 12 is to replace the controller.

Because the current sensor is installed inside the controller, replacing or repairing the sensor itself is generally not a normal user-service procedure.

Diagnosis	Solution
Error Code 12 is displayed and the motor cannot operate.	Replace the controller.
You are unsure whether the controller is defective.	Have the controller and electrical system professionally diagnosed before replacing components.

When replacing the controller, make sure the replacement is compatible with the specific Bafang motor system, battery voltage, display, and other electrical components.

Important: Do not install a higher-current controller simply to bypass Error Code 12. The controller's current limits are part of the motor and battery protection system.

Step 2: Clear Error Code 12

After replacing the controller:

1. Connect all components correctly.
2. Make sure all electrical connectors are securely seated.
3. Turn on the eBike system.
4. Check the display for Error Code 12.

Result	Next Action
Error Code 12 is inactive.	The repair is complete.
Error Code 12 remains active.	Return to Step 1 and recheck the controller and its connections. If all troubleshooting steps have been completed and the error remains, contact Bafang or a qualified eBike technician.

Can You Keep Riding with Bafang Error Code 12?

Normally, no. When Error Code 12 is active, the system disables the motor because it cannot reliably monitor or control motor current.

You may still be able to pedal the bicycle manually if there are no mechanical problems, but the electrical drive system should not be considered operational until the fault has been diagnosed and repaired.

Quick Troubleshooting Summary

Error 12 → Controller current sensor fault detected → Motor is disabled → Replace or professionally inspect the controller → Reconnect all components → Turn on the system → Confirm Error Code 12 has cleared.

Error Code 13: Battery Temperature Sensor Fault

Error Code: 13
Cause: Fault with the temperature sensor inside the battery.
Result: The display shows Error Code 13, and the motor cannot operate.

What Does Bafang Error Code 13 Mean?

Bafang Error Code 13 indicates that the eBike system has detected a fault with the temperature sensor inside the battery.

The battery temperature sensor continuously monitors the internal temperature of the battery pack. This information helps the system protect the lithium-ion cells against unsafe operating temperatures.

The sensor is installed inside the battery pack. If the system cannot receive a valid temperature reading from the sensor, Error Code 13 appears and motor assistance is disabled.

This is different from a battery simply being too hot or too cold. Error Code 13 specifically indicates a temperature-sensor fault.

Common Symptoms

When Error Code 13 occurs, you may notice:

• The display shows 13.
• The motor does not work.
• Pedal assistance is unavailable.
• The throttle, if equipped, does not operate the motor.
• The error may appear immediately after startup.
• Restarting the eBike may not clear the error.
• Allowing the battery to return to room temperature may not solve the problem if the sensor itself is faulty.

How to Fix Bafang Error Code 13

Step 1: Replace the Battery

According to Bafang's troubleshooting procedure, the recommended solution for Error Code 13 is to replace the battery.

Because the temperature sensor is located inside the battery pack, it is not normally considered a user-serviceable component.

Diagnosis	Solution
Error Code 13 is displayed and the motor cannot operate.	Replace the battery.
You want to confirm the diagnosis before buying a replacement battery.	Have the battery professionally tested by a Bafang dealer or qualified eBike technician.

Make sure any replacement battery is compatible with the specific Bafang drive system, including the required voltage, communication protocol, connector, mounting system, and battery management system.

Safety Warning: Do not open a lithium-ion eBike battery to access or repair the temperature sensor yourself. Battery packs can retain dangerous levels of electrical energy and may present fire, electric-shock, and short-circuit risks if improperly serviced.

Step 2: Clear Error Code 13

After replacing the battery:

1. Connect all components correctly.
2. Make sure the battery is properly installed and securely connected.
3. Turn on the eBike system.
4. Check whether Error Code 13 is still displayed.

Result	Next Action
Error Code 13 is inactive.	The repair is complete.
Error Code 13 remains active.	Return to Step 1 and recheck the battery and connections. If all troubleshooting steps have been completed and the error remains, contact Bafang or an authorized service provider.

Battery Temperature vs. Temperature Sensor Fault

It is important to distinguish between an actual battery temperature problem and a sensor failure.

A battery that becomes extremely hot or cold may temporarily limit eBike performance. Error Code 13, however, indicates that the system has detected a fault with the battery's internal temperature sensor, rather than simply reporting that the battery is outside its ideal operating temperature.

For this reason, simply waiting for the battery to cool down may not resolve Error Code 13.

Quick Troubleshooting Summary

Error 13 → Battery temperature sensor fault detected → Motor is disabled → Replace or professionally inspect the battery → Reconnect the battery and other components → Turn on the system → Confirm Error Code 13 has cleared.

Error Code 14: Controller Over-Temperature

Error Code: 14
Cause: The temperature inside the controller has reached its maximum protection value.
Result: The display shows Error Code 14, and the motor cannot operate.

What Does Bafang Error Code 14 Mean?

Bafang Error Code 14 indicates that the controller has become too hot and the system's thermal protection has been activated.

A temperature sensor installed inside the controller continuously monitors its internal temperature. When the controller reaches its maximum protection threshold, the system disables the motor to help prevent damage to the controller and other electrical components.

The diagnostic system runs continuously after the eBike is switched on.

In many cases, Error Code 14 is temporary and will disappear after the eBike and controller have had sufficient time to cool down.

Common Symptoms

When Error Code 14 occurs, you may notice:

• The display shows 14.
• The motor suddenly stops providing assistance.
• Pedal assist does not work.
• The throttle, if equipped, cannot power the motor.
• The problem occurs after a long or demanding ride.
• The system may return to normal after cooling down.

What Can Cause the Controller to Overheat?

Controller overheating is more likely when the electrical system is operating under sustained heavy load. Possible contributing factors include:

• Long or steep hill climbs
• Extended high-power riding
• Heavy rider or cargo loads
• Frequent hard acceleration
• Riding at low speeds under heavy motor load
• High ambient temperatures
• Insufficient cooling around the controller

If Error Code 14 occurs repeatedly during ordinary riding, the drive system should be professionally inspected.

How to Fix Bafang Error Code 14

Step 1: Turn Off the System and Let the eBike Cool Down

Stop riding and turn off the eBike system.

Allow the controller and other electrical components to cool naturally. Once the eBike has cooled down, restart the system and check whether Error Code 14 has disappeared.

Result	Solution
The system returns to normal after cooling down.	Go to Step 2 and confirm the error has cleared.
The system does not return to normal after cooling down.	According to the supplied Bafang troubleshooting procedure, replace the motor.

Note: Because Error Code 14 concerns controller temperature but the supplied Bafang procedure specifies motor replacement if cooling does not solve the problem, follow the service documentation for your exact Bafang drive system. On systems where the controller is integrated into the motor assembly, replacement may involve the complete drive unit.

Step 2: Clear Error Code 14

After the system has cooled down or the required component has been replaced:

1. Connect all components correctly.
2. Turn on the eBike system.
3. Check the display.
4. Confirm that motor assistance has returned.

Result	Next Action
Error Code 14 is inactive.	The repair is complete.
Error Code 14 remains active.	Return to Step 1. If all troubleshooting steps have already been completed, contact Bafang or a qualified Bafang service provider.

Error Code 10 vs. Error Code 14

Both codes indicate overheating, but they refer to different parts of the drive system:

Error Code	Meaning	First Action
10	Motor temperature has reached its maximum protection value.	Turn off the eBike and allow the motor to cool.
14	Controller temperature has reached its maximum protection value.	Turn off the eBike and allow the system/controller to cool.

If either error repeatedly returns during normal riding, simply resetting the system is not enough—the cause of the repeated overheating should be investigated.

Quick Troubleshooting Summary

Error 14 → Controller over-temperature detected → Motor is disabled → Turn off the eBike → Allow the system to cool naturally → Restart the system → If Error 14 clears, normal operation can resume → If it remains active after cooling, follow the Bafang service procedure for your specific drive unit or contact Bafang.

Error Code 15: Controller Temperature Sensor Fault

Error Code: 15
Cause: Fault with the temperature sensor inside the controller.
Result: The display shows Error Code 15, and the motor cannot operate.

What Does Bafang Error Code 15 Mean?

Bafang Error Code 15 indicates a problem with the temperature sensor inside the controller.

The controller temperature sensor monitors the controller's internal temperature. This allows the eBike system to detect unsafe temperatures and protect the controller and motor from potential thermal damage.

The temperature sensor is installed inside the controller, and the diagnostic system continuously monitors it after the eBike is turned on.

If the system detects an abnormal temperature-sensor signal, it displays Error Code 15 and disables the motor.

Common Symptoms

When Error Code 15 occurs, you may notice:

• The display shows 15.
• The motor does not provide assistance.
• Pedal assist stops working.
• The throttle, if equipped, cannot operate the motor.
• The error may appear immediately after startup.
• Restarting the system may temporarily or permanently clear the error.
• If the temperature sensor is defective, the error may remain even after the eBike has completely cooled down.

How to Fix Bafang Error Code 15

Step 1: Turn Off the System and Allow It to Cool

Turn off the eBike and allow the system to cool down naturally.

Once the controller and other electrical components have cooled, restart the eBike and check the display.

Result	Solution
The system returns to normal after cooling and restarting.	Proceed to Step 2 and confirm that Error Code 15 has cleared.
The system does not return to normal after cooling.	Replace or professionally inspect the controller.

Although Error Code 15 indicates a sensor fault rather than simply an overheating condition, cooling and restarting the system is the first troubleshooting step specified by Bafang.

Step 2: Clear Error Code 15

After cooling the system or replacing the controller:

1. Connect all components correctly.
2. Make sure the controller connections are securely seated.
3. Turn on the eBike system.
4. Check whether Error Code 15 is still displayed.

Result	Next Action
Error Code 15 is inactive.	The repair is complete.
Error Code 15 remains active.	Return to Step 1. If the controller has already been checked or replaced and the error remains, contact Bafang or a qualified service technician.

Error Code 14 vs. Error Code 15

These two codes are closely related but indicate different problems:

Error Code	Meaning	Typical First Step
14	Controller has reached its maximum temperature protection value.	Turn off the system and allow it to cool.
15	Controller temperature sensor fault.	Cool and restart the system; replace the controller if the fault remains.

In simple terms, Error 14 means the controller is too hot, while Error 15 means there is a problem with the sensor responsible for measuring controller temperature.

What If Error Code 15 Keeps Coming Back?

If Error Code 15 disappears after a restart but repeatedly returns, the controller's temperature sensing system may have an intermittent fault.

Because the sensor is located inside the controller, internal diagnosis or repair should generally be performed by a qualified technician. Replacing the controller may be necessary if the sensor continues to produce an invalid reading.

Quick Troubleshooting Summary

Error 15 → Controller temperature sensor fault detected → Turn off the eBike → Allow the system to cool → Restart → If Error 15 clears, check operation → If it remains active, replace or professionally inspect the controller → Reconnect all components → Confirm the error has cleared.

Error Code 21: Speed Sensor Fault

Error Code: 21
Cause: Speed sensor fault.
Result: The display shows Error Code 21, and the motor cannot operate.

What Does Bafang Error Code 21 Mean?

Bafang Error Code 21 indicates that the eBike system has detected a problem with the speed sensor or its signal.

The speed sensor measures the speed of the eBike and sends this information to the drive system. According to Bafang's documentation, the speed sensor is installed on the frame near the left side of the rear wheel spokes. The diagnostic system continuously checks the sensor after the eBike is turned on.

If the system cannot correctly detect the speed signal, Error Code 21 appears and the motor may be disabled.

Common Symptoms

When Error Code 21 occurs, you may notice:

• The display shows 21.
• The motor does not provide assistance.
• The speedometer may show 0 even while the bike is moving.
• Pedal assistance may stop working.
• The problem may appear after the rear wheel, sensor, or magnet has been moved or adjusted.
• The error may disappear temporarily after restarting the system.

How to Fix Bafang Error Code 21

Step 1: Restart the eBike

Start with a simple system restart.

1. Turn the eBike off.
2. Wait briefly.
3. Turn the system back on.
4. Check whether Error Code 21 returns.

If the system returns to normal, continue to the final error-code check. If it does not, inspect the magnet and speed sensor.

Step 2: Check the Magnet and Speed Sensor Alignment

Inspect the magnet on the rear wheel and the speed sensor mounted on the frame.

According to the Bafang troubleshooting documentation, the clearance between the magnet and speed sensor should be 10–20 mm, and the magnet should be correctly aligned with the sensor.

Inspection Result	Solution
Clearance is 10–20 mm and alignment is correct.	Continue to Step 3.
Clearance is outside 10–20 mm or the magnet is misaligned.	Adjust the magnet until the clearance is 10–20 mm and it aligns with the sensor. Then restart and check the system.

A displaced wheel magnet is one of the first physical components to check when Error Code 21 suddenly appears.

Step 3: Inspect the Speed Sensor Connector and Cable

Check the speed sensor connector and wiring carefully.

Look for:

• Loose connectors
• Corroded pins
• Bent pins
• Broken pins
• Dirt or debris inside the connector
• Damaged wire insulation
• Broken connector housing

Bafang specifies that damaged connections should be cleaned and repaired where possible before continuing with diagnosis.

Inspection Result	Solution
Connector and wiring are correctly connected.	Continue to Step 4.
Damaged or contaminated connection is found.	Clean the connector and pins. Repair the harness, connector, or pins if possible.

Step 4: Check the Speed Sensor Signal with BESST

Connect the eBike to the Bafang BESST diagnostic tool and check the speed sensor signal.

BESST Result	Next Action
Speed sensor signal is normal.	Continue to Step 5.
No speed sensor signal is received.	Go to Step 6.

This test helps determine whether the problem is with the sensor itself or elsewhere in the drive system.

Step 5: Update the Controller with BESST

If the speed sensor signal is normal, use BESST to update the controller.

Result	Next Action
System returns to normal after the update.	Proceed to Step 8.
System still does not work normally.	Continue to Step 6.

Step 6: Replace the Speed Sensor

If the system cannot receive a proper speed sensor signal, replace the speed sensor.

After replacement, restart the eBike and test the system.

Result	Next Action
System returns to normal.	Proceed to Step 8.
System still does not return to normal.	Continue to Step 7.

Step 7: Replace or Professionally Inspect the Motor

If replacing the speed sensor does not solve Error Code 21, Bafang's troubleshooting procedure specifies motor replacement as the next step.

At this point, professional diagnosis is advisable before purchasing major replacement components.

Step 8: Clear Error Code 21

After completing the appropriate repair:

1. Connect all components.
2. Turn on the eBike system.
3. Check the display.
4. Confirm that the motor operates normally.

Result	Next Action
Error Code 21 is inactive.	Repair complete.
Error Code 21 remains active.	Return to Step 1 and repeat the checks. If all steps have been completed, contact Bafang or an authorized service provider.

This is the final verification procedure specified in the Bafang troubleshooting documentation.

Quick Troubleshooting Summary

Error 21 → Restart the eBike → Check rear-wheel magnet → Set magnet-to-sensor clearance to 10–20 mm → Check sensor cable and connector → Test sensor signal with BESST → Update controller if signal is normal → Replace speed sensor if necessary → If the fault remains, inspect/replace the motor → Restart and confirm Error Code 21 has cleared.

For riders troubleshooting at home, the magnet alignment, sensor clearance, connector, and wiring are the most practical things to check first. BESST diagnostics and motor replacement are better handled by a Bafang dealer or qualified eBike technician.

Error Code 25: Torque Signal Fault

Error Code: 25
Cause: Torque signal fault.
Result: The display shows Error Code 25, and the motor cannot operate.

What Does Bafang Error Code 25 Mean?

Bafang Error Code 25 indicates that the eBike system has detected a problem with the torque sensor signal.

The torque sensor measures the amount of force the rider applies to the pedals. The motor controller uses this information to determine how much assistance to provide.

According to Bafang's documentation, the torque sensor is installed between the pedals, and its diagnostic check runs continuously after the system is turned on. If the system cannot receive a valid torque signal, Error Code 25 appears and the motor cannot operate.

Common Symptoms

When Error Code 25 occurs, you may notice:

• The display shows 25.
• The motor does not provide assistance.
• Pedal assist does not respond to pedaling force.
• Motor assistance may stop suddenly.
• Restarting the eBike may not clear the error.
• The problem may be caused by a loose or damaged torque sensor connection.

How to Fix Bafang Error Code 25

Step 1: Check the Torque Sensor Connector

Start by inspecting the torque sensor cable and connectors.

Look for:

• Loose connectors
• Corroded pins
• Bent or broken pins
• Dirt or debris inside the connector
• Damaged wire insulation
• Broken connector housing

Bafang recommends cleaning contaminated connectors and repairing damaged wiring, connectors, or pins when possible.

Inspection Result	Solution
Torque sensor is correctly connected and no damage is found.	Continue to Step 2.
A damaged or contaminated connection is found.	Clean the connector and pins. Repair the damaged harness, connector, or pins if possible, then check whether the error clears.

When reconnecting the sensor, make sure the connector is correctly aligned and fully seated. Do not force connectors together, as this can bend or damage the pins.

Step 2: Check the Torque Sensor Signal with BESST

Connect the eBike to the Bafang BESST diagnostic tool and check the torque sensor signal.

BESST Result	Next Action
Torque sensor signal is normal.	Continue to Step 3.
No signal can be received from the torque sensor.	Go to Step 4.

This diagnostic step helps determine whether the torque sensor is communicating correctly with the drive system.

Step 3: Update the Controller with BESST

If BESST shows that the torque sensor signal is normal, use the tool to update the controller.

Result	Next Action
The system returns to normal after the update.	Proceed to Step 5.
The system still does not return to normal.	Continue to Step 4.

Step 4: Replace the Torque Sensor

If BESST cannot receive a torque sensor signal, or updating the controller does not solve the problem, Bafang's troubleshooting procedure specifies replacing the torque sensor.

Because the torque sensor is part of the pedal/crank area and may be integrated into the drive system, replacement may require specialized tools and knowledge. If you are unfamiliar with eBike drive-system servicing, have this step performed by a Bafang dealer or qualified technician.

Step 5: Clear Error Code 25

After repairing the connection, updating the controller, or replacing the torque sensor:

1. Connect all components.
2. Make sure all connectors are securely seated.
3. Turn on the eBike system.
4. Check the display.
5. Test pedal assistance.

Result	Next Action
Error Code 25 is inactive.	The repair is complete.
Error Code 25 remains active.	Return to Step 1 and repeat the checks. If all steps have been completed, contact Bafang or an authorized service provider.

This is the final verification procedure specified by Bafang.

Quick Troubleshooting Summary

Error 25 → Check torque sensor cable and connectors → Clean or repair damaged connections → Test torque sensor signal with BESST → If signal is normal, update the controller → If there is no signal or the update does not solve the problem, replace the torque sensor → Reconnect all components → Restart the system → Confirm Error Code 25 has cleared.

Error Code 26: Torque Sensor Speed Signal Fault

Error Code: 26
Cause: The speed signal from the torque sensor has an error.
Result: The display shows Error Code 26, and the motor cannot operate.

What Does Bafang Error Code 26 Mean?

Bafang Error Code 26 indicates that the eBike system has detected a problem with the speed/cadence signal from the torque sensor.

According to Bafang's documentation, the torque sensor is integrated with a cadence sensor that measures the rider's pedaling cadence. The torque sensor assembly is installed between the pedals.

After the eBike is turned on, the diagnostic system continuously monitors this signal. If the system detects an abnormal or missing speed signal from the torque sensor, Error Code 26 appears and the motor cannot operate.

Common Symptoms

When Error Code 26 occurs, you may notice:

• The display shows 26.
• The motor does not provide assistance.
• Pedal assist does not respond normally.
• The system may fail to detect pedaling cadence.
• Motor assistance may stop unexpectedly.
• Restarting the eBike may not clear the error.

How to Fix Bafang Error Code 26

Step 1: Check All Connectors on the eBike

Bafang's first troubleshooting step is to inspect all relevant cables and connectors on the eBike.

Look for:

• Loose connectors
• Corroded pins
• Bent pins
• Broken pins
• Dirt or debris inside connectors
• Damaged wire insulation
• Broken connector housings

If a damaged connection is found, clean the connector and pins and repair the damaged harness, connector, or pins if possible.

Inspection Result	Solution
All connectors are correctly connected.	Continue to Step 2.
A damaged or contaminated connection is found.	Clean and repair the connector, pins, or wiring where possible, then check whether the error clears.

Step 2: Check the Torque Sensor Speed Signal with BESST

Connect the eBike to the Bafang BESST diagnostic tool and check the signal from the torque sensor.

BESST Result	Next Action
The speed signal is normal.	Continue to Step 3.
BESST cannot read the speed signal from the torque sensor.	Go to Step 4.

Step 3: Replace the Display

If BESST indicates that the torque sensor speed signal is normal, Bafang's troubleshooting procedure specifies replacing the display as the next step.

Result	Next Action
The system returns to normal after replacing the display.	Go to Step 6.
The system still does not return to normal.	Continue to Step 4.

This step is important because Error Code 26 does not necessarily mean that the torque sensor itself has failed. If its speed signal is normal, another component in the system may be responsible.

Step 4: Update the Controller with BESST

Use the Bafang BESST tool to update the controller.

Result	Next Action
The system returns to normal after the controller update.	Go to Step 6.
The system does not return to normal after the update.	Continue to Step 5.

Step 5: Replace the Torque Sensor

If checking the connectors, diagnosing the speed signal, and updating the controller do not solve the problem, Bafang specifies replacing the torque sensor.

Because the torque sensor is located around the pedal/crank area and may be integrated into the drive system, replacement is generally better handled by a Bafang dealer or qualified eBike technician.

Step 6: Clear Error Code 26

After completing the appropriate repair:

1. Connect all components correctly.
2. Make sure every connector is securely seated.
3. Turn on the eBike system.
4. Check whether Error Code 26 is still displayed.
5. Test pedal assistance.

Result	Next Action
Error Code 26 is inactive.	The repair is complete.
Error Code 26 remains active.	Return to Step 1 and repeat the diagnostic procedure. If all steps have been completed and checked, contact Bafang.

Error Code 25 vs. Error Code 26

Although both codes involve the torque sensor, they refer to different signals:

Error Code	Meaning
25	Torque signal fault — the system has a problem with the signal used to measure pedal force.
26	Torque sensor speed signal fault — the system has a problem with the cadence/speed signal associated with the torque sensor.

So, Error 25 is primarily related to pedal-force measurement, while Error 26 is related to the torque sensor's integrated cadence/speed signal.

Quick Troubleshooting Summary

Error 26 → Check all connectors and wiring → Test the torque sensor speed signal with BESST → If the signal is normal, replace/test the display → Update the controller → If the problem remains, replace the torque sensor → Reconnect all components → Restart the system → Confirm Error Code 26 has cleared.

Error Code 27: Controller Over-Current

Error Code: 27
Cause: Over-current of the controller.
Result: The display shows Error Code 27, and the motor cannot operate.

What Does Bafang Error Code 27 Mean?

Bafang Error Code 27 indicates that the eBike system has detected an over-current condition in the controller.

The controller is the core electronic component responsible for controlling the motor's operation and speed. Its physical location varies depending on the Bafang drive system and eBike model.

After the system is turned on, diagnostics run continuously. If a controller over-current fault is detected, the display shows Error Code 27 and the motor is disabled.

Common Symptoms

When Error Code 27 occurs, you may notice:

• The display shows 27.
• The motor does not operate.
• Pedal assistance is unavailable.
• The throttle, if equipped, cannot power the motor.
• The error may return immediately after restarting the eBike.
• The motor remains disabled while the fault is active.

How to Fix Bafang Error Code 27

Step 1: Update the Controller with BESST

Connect the eBike to the Bafang BESST diagnostic tool and update the controller.

After the update is complete, restart the system and check whether normal operation has returned.

Result	Solution
The system returns to normal after the controller update.	Continue to Step 2.
The system does not return to normal after the update.	Replace the controller.

Bafang's troubleshooting procedure specifically recommends a controller update first, followed by controller replacement if the update does not resolve Error Code 27.

Because BESST is a Bafang diagnostic/service tool, riders without access to it may need to have this procedure performed by a Bafang dealer or qualified eBike technician.

Step 2: Clear Error Code 27

After updating or replacing the controller:

1. Connect all components correctly.
2. Make sure all connectors are securely seated.
3. Turn on the eBike system.
4. Check whether Error Code 27 is still displayed.
5. Confirm that motor assistance works normally.

Result	Next Action
Error Code 27 is inactive.	The repair is complete.
Error Code 27 remains active.	Return to Step 1. If all troubleshooting steps have already been completed and checked, contact Bafang.

Error Code 12 vs. Error Code 27

Bafang Error Codes 12 and 27 are both related to motor current, but they indicate different faults:

Error Code	Meaning	Recommended Solution
12	Controller current sensor fault	Replace the controller.
27	Controller over-current	Update the controller with BESST; replace the controller if the problem remains.

In other words, Error 12 indicates a fault with the component that senses current, while Error 27 indicates that the controller has detected an over-current condition.

Quick Troubleshooting Summary

Error 27 → Controller over-current detected → Motor is disabled → Connect the eBike to BESST → Update the controller → Restart the system → If the problem remains, replace the controller → Reconnect all components → Confirm Error Code 27 has cleared.

Error Code 30: Communication Failed

Error Code: 30
Cause: Communication failure.
Result: The display shows Error Code 30, and the motor cannot operate.

What Does Bafang Error Code 30 Mean?

Bafang Error Code 30 indicates a communication failure between components in the eBike electrical system.

The display provides information such as battery voltage, speed, riding status, light status, and fault information from different electrical components. It is installed on the handlebar.

After the eBike is switched on, the system continuously runs diagnostics. If communication fails, the display shows Error Code 30 and the motor cannot operate. Once the communication problem is corrected and the diagnostic test passes, the system should return to normal.

Common Symptoms

When Error Code 30 occurs, you may notice:

• The display shows 30.
• The motor does not provide assistance.
• Pedal assist stops working.
• The throttle, if equipped, cannot drive the motor.
• Information on the display may not update correctly.
• The error may appear after a connector or wiring problem.
• Restarting the eBike may not permanently clear the fault.

Because Code 30 is a communication error, the problem is not necessarily caused by the motor itself. The wiring, connectors, display, or EB-BUS may be responsible.

How to Fix Bafang Error Code 30

Step 1: Check All Connectors on the eBike

Bafang's first troubleshooting step is to inspect all cables and connectors on the eBike.

Check for:

• Loose connectors
• Corroded pins
• Bent pins
• Broken pins
• Dirt or debris inside connectors
• Damaged wire insulation
• Broken connector housings

If a damaged connection is found, Bafang recommends cleaning the connector and pins and repairing the damaged harness, connector, or pins where possible.

Inspection Result	Solution
All connectors are correctly connected.	Continue to Step 2.
A damaged connection is found.	Clean the connector and pins. Repair damaged wiring, connectors, or pins if possible, then proceed to the final error check.

When reconnecting components, make sure connectors are correctly aligned and fully seated. Avoid forcing connectors together, especially if the pins appear bent.

Step 2: Diagnose the System with BESST

Connect the eBike to the Bafang BESST diagnostic tool and run a system diagnosis.

BESST Result	Next Action
BESST identifies the problem.	Repair the identified problem, then proceed to Step 5.
BESST does not identify the problem.	Continue to Step 3.

This diagnostic step can help determine which component is interrupting communication within the Bafang system.

Step 3: Replace the Display

If BESST does not identify the cause, Bafang's next troubleshooting step is to replace the display.

After installing a compatible display, restart the eBike and check whether communication has been restored.

Result	Next Action
The system returns to normal.	Go to Step 5.
The system still does not return to normal.	Continue to Step 4.

Before purchasing a new display, make sure it is compatible with your specific Bafang drive system and communication protocol.

Step 4: Replace the EB-BUS

If replacing the display does not resolve Error Code 30, Bafang specifies replacing the EB-BUS as the next troubleshooting step.

The EB-BUS is part of the communication connection between electrical components. A damaged cable, connector, or internal connection can prevent components from communicating correctly.

Step 5: Clear Error Code 30

After completing the appropriate repair:

1. Connect all components correctly.
2. Check that every connector is fully seated.
3. Turn on the eBike system.
4. Check the display.
5. Confirm that motor assistance operates normally.

Result	Next Action
Error Code 30 is inactive.	The repair is complete.
Error Code 30 remains active.	Return to Step 1 and repeat the diagnostic procedure. If all steps have been completed and checked, contact Bafang.

This is the final verification procedure specified in Bafang's troubleshooting documentation.

What Should You Check First at Home?

For riders without a BESST diagnostic tool, the most practical first step is a careful inspection of the electrical connections.

Turn the eBike off and check accessible connectors for looseness, dirt, corrosion, damaged wiring, or bent pins. If everything appears correctly connected but Error Code 30 remains, further diagnosis may require BESST and professional service.

Avoid randomly replacing the motor, battery, or controller, because Bafang's troubleshooting sequence first points to connections, BESST diagnosis, the display, and finally the EB-BUS.

Quick Troubleshooting Summary

Error 30 → Check all cables and connectors → Clean or repair damaged connections → Diagnose the system with BESST → Repair any fault identified by BESST → If no fault is identified, replace/test the display → If the problem remains, replace the EB-BUS → Reconnect all components → Restart the system → Confirm Error Code 30 has cleared.

Error Code 33: Brake Detection Circuit Fault

Error Code: 33
Cause: Brake detection circuit fault.
Result: The display shows Error Code 33, and the electronic brake cannot operate normally.

What Does Bafang Error Code 33 Mean?

Bafang Error Code 33 indicates that the system has detected a fault in the electronic brake detection circuit.

The electronic brake system is designed to improve braking performance while keeping the electrical system relatively simple. The electronic brake cable is one component of the EB-BUS cable, while the electronic brake controls are installed on the handlebar.

After the eBike is turned on, the diagnostic system continuously monitors the brake circuit. If it detects an abnormal brake signal or circuit fault, Error Code 33 appears and the electronic brake may not work normally.

Common Symptoms

When Error Code 33 occurs, you may notice:

• The display shows 33.
• The electronic brake does not work normally.
• The brake-related electrical function may respond inconsistently.
• The error remains after restarting the eBike.
• A brake connector may be loose, dirty, corroded, or damaged.
• The brake wiring or connector pins may be damaged.

How to Fix Bafang Error Code 33

Step 1: Check the Brake Connectors

Inspect the electronic brake cables and connectors carefully.

Look for:

• Loose connectors
• Corroded pins
• Bent pins
• Broken pins
• Dirt or debris inside the connector
• Damaged wire insulation
• Broken connector housings

Turn the eBike off before disconnecting or inspecting electrical connectors.

Inspection Result	Solution
Connector or pins are dirty or damaged.	Clean the connector and pins. Repair the damaged harness, connector, or pins if possible.
Connectors are correctly connected and no connection problem is found.	Replace the brakes.

When reconnecting the brake cables, make sure each connector is properly aligned and fully seated. Do not force a connector together if the pins are bent or misaligned.

Step 2: Clear Error Code 33

After cleaning or repairing the connection, or replacing the brakes:

1. Connect all components correctly.
2. Make sure the electronic brake connectors are securely seated.
3. Turn on the eBike system.
4. Check the display.
5. Verify that the electronic brake operates normally.

Result	Next Action
Error Code 33 is inactive.	The repair is complete.
Error Code 33 remains active.	Return to Step 1 and recheck the brake connectors and components. If all troubleshooting steps have been completed and checked, contact Bafang.

What Should You Check First?

Because Bafang's troubleshooting procedure starts with the brake connectors, do not immediately replace the brake components when Error Code 33 appears.

First inspect the brake wiring and connectors for contamination or physical damage. A loose connection, corroded pin, bent pin, or damaged cable can interrupt the brake detection circuit and trigger the error.

If the connections are correct but Error Code 33 remains, Bafang's specified next action is to replace the brakes.

Quick Troubleshooting Summary

Error 33 → Turn off the eBike → Check electronic brake cables and connectors → Look for loose, corroded, dirty, bent, or broken connections → Clean or repair damaged connectors/wiring → If connections are correct, replace the brakes → Reconnect all components → Turn on the system → Confirm Error Code 33 has cleared.

Error Code 35: 15V Detection Circuit Error

Error Code: 35
Cause: The detection circuit for 15V has an error.
Result: The display shows Error Code 35.

What Does Bafang Error Code 35 Mean?

Bafang Error Code 35 indicates that the eBike system has detected an error with the 15V detection circuit.

According to Bafang's troubleshooting information, the battery serves as the onboard power source that supplies energy to the eBike. The battery is typically installed on the bike frame.

After the eBike is switched on, the diagnostic system continuously monitors the electrical system. If a problem with the 15V detection circuit is detected, Error Code 35 appears on the display.

Once the fault has been corrected and the system passes its diagnostic check, normal operation should resume.

Common Symptoms

When Error Code 35 occurs, you may notice:

• The display shows 35.
• The error returns after restarting the eBike.
• Normal electrical operation may be affected.
• Updating the controller may clear the fault.
• If the error remains after the update, the controller may need to be replaced.

How to Fix Bafang Error Code 35

Step 1: Update the Controller with BESST

Connect the eBike to the Bafang BESST diagnostic tool and update the controller.

After completing the controller update, restart the system and check whether Error Code 35 is still present.

Result	Solution
The system returns to normal after the controller update.	Continue to Step 2.
The system does not return to normal after the update.	Replace the controller.

Bafang's troubleshooting procedure therefore recommends updating the controller before replacing any components.

If you do not have access to BESST, this procedure may need to be performed by a Bafang dealer or qualified eBike technician.

Step 2: Clear Error Code 35

After updating or replacing the controller:

1. Connect all components correctly.
2. Make sure the electrical connectors are securely seated.
3. Turn on the eBike system.
4. Check the display for Error Code 35.

Result	Next Action
Error Code 35 is inactive.	The repair is complete.
Error Code 35 remains active.	Return to Step 1 and repeat the troubleshooting procedure. If all steps have been completed and checked, contact Bafang.

Do You Need to Replace the Controller Immediately?

Not necessarily.

Bafang's troubleshooting sequence specifies that the controller should first be updated using BESST. Controller replacement is recommended only if the system does not return to normal after the update.

Therefore, the troubleshooting order should be:

BESST diagnosis/update first → controller replacement only if the problem remains.

This can help avoid replacing an expensive component unnecessarily.

Quick Troubleshooting Summary

Error 35 → 15V detection circuit error → Connect the eBike to BESST → Update the controller → Restart the system → If the system returns to normal, clear and verify the error → If Error 35 remains, replace the controller → Reconnect all components → Confirm Error Code 35 has cleared.

Error Code 36: Keypad Detection Circuit Error

Error Code: 36
Cause: The detection circuit on the keypad has an error.
Result: The display shows Error Code 36.

What Does Bafang Error Code 36 Mean?

Bafang Error Code 36 indicates that the eBike system has detected a problem with the keypad detection circuit.

The keypad is the set of buttons used to operate and interact with the eBike display. After the system is turned on, Bafang's diagnostic system continuously monitors the keypad circuit. If a fault is detected, Error Code 36 appears on the display.

The problem may involve the display connector or wiring, the display itself, or the controller.

Common Symptoms

When Error Code 36 occurs, you may notice:

• The display shows 36.
• Keypad buttons may not respond correctly.
• Display controls may behave abnormally.
• The error may remain after restarting the eBike.
• A loose or damaged display connector may be present.
• Updating the controller may resolve the problem in some cases.

How to Fix Bafang Error Code 36

Step 1: Check the Display Connector

Start by inspecting the display cable and connectors.

Bafang specifies checking for:

• Loose connectors
• Corroded pins
• Bent pins
• Broken pins
• Dirt or debris inside the connector
• Damaged wire insulation
• Broken connector housing

If damage or contamination is found, clean the connector and pins and repair the damaged harness, connector, or pins where possible.

Inspection Result	Solution
Display connector is correctly connected.	Continue to Step 2.
A damaged or contaminated connection is found.	Clean the connector and pins. Repair damaged wiring, connectors, or pins if possible, then proceed to Step 5.

Turn off the eBike before disconnecting electrical connectors, and make sure the pins are correctly aligned before reconnecting them.

Step 2: Update the Controller with BESST

If the display connection is correct, connect the eBike to the Bafang BESST diagnostic tool and update the controller.

Result	Next Action
The system returns to normal after the update.	Go to Step 5.
The system does not return to normal after the update.	Continue to Step 3.

If you do not have access to BESST, this step may need to be performed by a Bafang dealer or qualified eBike technician.

Step 3: Replace the Display

If updating the controller does not solve Error Code 36, Bafang specifies replacing the display.

Result	Next Action
The system returns to normal after replacing the display.	Go to Step 5.
The system still does not return to normal.	Continue to Step 4.

Make sure the replacement display is compatible with your specific Bafang drive system and communication protocol.

Step 4: Replace the Controller

If replacing the display still does not resolve the problem, Bafang's next troubleshooting step is to replace the controller.

Because controller replacement involves the eBike's main electrical system, professional diagnosis is advisable before purchasing a replacement component.

Step 5: Clear Error Code 36

After completing the appropriate repair:

1. Connect all components correctly.
2. Make sure all connectors are securely seated.
3. Turn on the eBike system.
4. Check whether Error Code 36 is still displayed.
5. Test the keypad buttons and display operation.

Result	Next Action
Error Code 36 is inactive.	The repair is complete.
Error Code 36 remains active.	Return to Step 1 and repeat the checks. If all steps have been completed and checked, contact Bafang.

What Should You Check First at Home?

Before replacing the display or controller, carefully inspect the display cable and connector. A loose connector, bent pin, corrosion, dirt, or damaged wiring can interrupt the keypad circuit and trigger Error Code 36.

The troubleshooting order specified by Bafang is:

Check display connector → Update controller with BESST → Replace display → Replace controller.

Following this sequence can help avoid replacing expensive components unnecessarily.

Quick Troubleshooting Summary

Error 36 → Check display cable and connector → Clean or repair damaged connections → Update the controller with BESST → If the problem remains, replace the display → If Error 36 still remains, replace the controller → Reconnect all components → Restart the system → Confirm Error Code 36 has cleared.

Error Code 37: WDT Circuit Fault

Error Code: 37
Cause: WDT circuit fault.
Result: The display shows Error Code 37, and the Watchdog Timer (WDT) cannot operate normally.

What Does Bafang Error Code 37 Mean?

Bafang Error Code 37 indicates that the Watchdog Timer (WDT) circuit is faulty.

The Watchdog Timer is a circuit used to monitor processor operation. If the processor stops operating correctly, the WDT can detect the problem and trigger a processor reset.

In the Bafang system, the WDT is associated with the controller and reports the status of the Watchdog Timer function. The system continuously runs diagnostics after the eBike is turned on.

If the WDT circuit cannot operate normally, Error Code 37 is displayed.

Note: The supplied Bafang text lists Error Code 37 in the title, cause, and troubleshooting section, but the "Error Phenomenon" line says "error code 27." This appears inconsistent within the supplied material. For this section, it is retained as Error Code 37 based on the surrounding documentation.

Common Symptoms

When Error Code 37 occurs, you may notice:

• The display shows 37.
• The WDT function does not operate normally.
• The eBike's electrical system may not operate correctly.
• The error may remain after restarting the system.
• Controller wiring or connectors may be dirty or damaged.
• If all connections are correct, the controller may need replacement.

How to Fix Bafang Error Code 37

Step 1: Check All Controller Connectors

Inspect the cables and connectors coming from the controller.

Check for:

• Loose connectors
• Corroded pins
• Bent pins
• Broken pins
• Dirt or debris inside connectors
• Damaged wire insulation
• Broken connector housings

Turn off the eBike before disconnecting or inspecting electrical connectors.

Inspection Result	Solution
Controller connections are correct and no connector problem is found.	Replace the controller.
Connector pins are dirty or damaged.	Clean the connector and pins. Repair the damaged harness, connector, or pins if possible.

When reconnecting the controller, make sure each connector is properly aligned and securely seated. Do not force connectors together if the pins are bent or damaged.

Step 2: Clear Error Code 37

After repairing the connection or replacing the controller:

1. Connect all components correctly.
2. Make sure all controller connectors are securely seated.
3. Turn on the eBike system.
4. Check whether Error Code 37 is still displayed.

Result	Next Action
Error Code 37 is inactive.	The repair is complete.
Error Code 37 remains active.	Return to Step 1 and repeat the checks. If all troubleshooting steps have been completed and checked, contact Bafang.

What Should You Check First?

Before replacing the controller, carefully inspect its wiring and connectors.

If you find dirt, corrosion, bent pins, broken pins, damaged insulation, or a broken connector, clean or repair the affected connection first.

If all controller connections are correct but Error Code 37 remains, the supplied Bafang troubleshooting procedure specifies controller replacement.

Quick Troubleshooting Summary

Error 37 → WDT circuit fault → Turn off the eBike → Inspect all controller cables and connectors → Clean or repair dirty/damaged connections → If connections are correct, replace the controller → Reconnect all components → Turn on the system → Confirm Error Code 37 has cleared.

Error Codes 41, 42, 43 & 44: Battery Voltage and Cell Voltage Faults

Bafang Error Codes 41, 42, 43, and 44 are battery-related faults. They indicate that the system has detected an abnormal total battery voltage, battery-cell condition, or individual cell voltage.

Error Code	Cause	Result
41 / 42	The total battery voltage is too high or too low.	The display shows Error Code 41/42, and the motor cannot operate.
43	The total battery cell power is too high.	The display shows Error Code 43, and the motor cannot operate.
44	The voltage of a single battery cell is too high.	The display shows Error Code 44, and the motor cannot operate normally.

What Do Bafang Error Codes 41 and 42 Mean?

Error Codes 41/42 indicate that the total voltage of the eBike battery is outside the system's expected range—it is either too high or too low.

When this condition is detected, the display shows Error Code 41 or 42 and the motor is disabled.

What Does Bafang Error Code 43 Mean?

Error Code 43 indicates that the system has detected an excessively high condition related to the total battery cells.

When Error Code 43 is active, the motor cannot operate.

What Does Bafang Error Code 44 Mean?

Error Code 44 indicates that the voltage of an individual battery cell is too high.

Unlike Codes 41 and 42, which concern the battery's total voltage, Code 44 specifically points to an abnormal voltage condition involving a single cell.

When this error is detected, the motor cannot operate normally.

Why Do These Battery Errors Stop the Motor?

The battery is the onboard power source that supplies energy to the eBike. According to the supplied Bafang troubleshooting information, the battery is installed on the bike frame.

After the system is switched on, diagnostics run continuously. If the battery-related diagnostic check detects one of these abnormal conditions, the corresponding error code appears.

Once the fault is corrected and the diagnostic check passes, the system can return to normal operation.

How to Fix Bafang Error Codes 41, 42, 43 and 44

Step 1: Replace the Battery

For all four error codes, the supplied Bafang troubleshooting procedure specifies the same first action:

Replace the battery.

Error Code	Recommended Action
41	Replace the battery.
42	Replace the battery.
43	Replace the battery.
44	Replace the battery.

These faults relate to conditions detected within the battery system, so the supplied troubleshooting procedure does not provide a user-level repair process for individual cells or internal battery components.

Safety Warning: Do not open the eBike battery or attempt to repair or replace individual lithium-ion cells yourself. Battery packs contain high-energy cells and should be serviced only by appropriately qualified professionals.

Step 2: Clear the Error Code

After replacing the battery:

1. Connect all components.
2. Make sure the battery is correctly installed.
3. Turn on the eBike system.
4. Check the display.
5. Confirm that the motor operates normally.

Result	Next Action
Error Code 41/42/43/44 is inactive.	The repair is complete.
Error Code 41/42/43/44 remains active.	Return to Step 1 and recheck the battery. If all steps have been completed and checked again, contact Bafang.

Error Codes 41 vs. 42 vs. 43 vs. 44

The easiest way to distinguish these battery-related Bafang error codes is by looking at what the system has detected:

Error Code	Battery Problem	Motor Status
41/42	Total battery voltage is too high/low	Motor cannot work
43	Total battery cell power is too high	Motor cannot work
44	Individual cell voltage is too high	Motor cannot work normally

Although the underlying conditions differ, the supplied Bafang troubleshooting procedure gives the same repair action for all four codes: replace the battery and then verify that the error has cleared.

Quick Troubleshooting Summary

Error 41/42/43/44 → Battery-related voltage/cell fault detected → Motor operation is disabled or abnormal → Replace the battery → Connect all components → Turn on the eBike → Check the display → If the error disappears, repair is complete → If the error remains, recheck the procedure or contact Bafang.

Error Code 45: Battery Temperature Is Too High

Error Code: 45
Cause: The battery temperature is too high.
Result: The display shows Error Code 45, and the motor cannot operate.

What Does Bafang Error Code 45 Mean?

Bafang Error Code 45 indicates that the temperature inside the eBike battery has become too high.

The battery contains an internal temperature sensor that detects the temperature inside the battery pack. After the eBike system is turned on, diagnostics run continuously to monitor this temperature.

If the detected battery temperature becomes too high, the display shows Error Code 45 and the motor is disabled.

Once the battery has cooled sufficiently and the diagnostic check passes, the system should return to normal operation.

Common Symptoms

When Error Code 45 occurs, you may notice:

• The display shows 45.
• The motor stops working.
• Pedal assistance is unavailable.
• The throttle, if equipped, cannot power the motor.
• The battery may feel unusually warm.
• The system may return to normal after the battery cools down.
• If cooling does not clear the error, the battery may need replacement.

How to Fix Bafang Error Code 45

Step 1: Turn Off the System and Let the Battery Cool Down

Turn off the eBike system and shut off the battery.

Allow the battery to cool down naturally. Once it has cooled, restart the system and check whether Error Code 45 has disappeared.

Result	Solution
The system returns to normal after cooling down.	Continue to Step 2.
The system does not return to normal after cooling down.	Replace the battery.

Do not continue trying to operate the motor while Error Code 45 is active.

Safety Warning: Do not attempt to rapidly cool the battery with water, ice, or other liquids. Do not open the battery pack. Allow it to cool naturally in a safe location.

Step 2: Clear Error Code 45

After the battery has cooled or been replaced:

1. Connect all components correctly.
2. Turn on the eBike system.
3. Ride the eBike for a period of time, as specified in the troubleshooting procedure.
4. Check whether Error Code 45 returns.

Result	Next Action
Error Code 45 is inactive.	The repair is complete.
Error Code 45 remains active.	Return to Step 1. If all troubleshooting steps have been completed and checked again, contact Bafang.

Error Code 13 vs. Error Code 45

Both errors involve the battery temperature system, but they indicate different conditions:

Error Code	Meaning	Troubleshooting Action
13	Battery temperature sensor fault	Replace the battery.
45	Battery temperature is too high	Turn off the system and battery and allow it to cool; replace the battery if the system does not return to normal.

In simple terms, Error 13 means there is a fault with the temperature sensor, while Error 45 means the sensor has detected that the battery itself is too hot.

Quick Troubleshooting Summary

Error 45 → Battery temperature is too high → Turn off the eBike and shut off the battery → Allow the battery to cool → Restart the system → If the system returns to normal, ride for a period and confirm the error does not return → If the system does not return to normal after cooling, replace the battery → If Error 45 remains active, contact Bafang.

Error Code 46: Battery Temperature Is Too Low

Error Code: 46
Cause: The battery temperature is too low.
Result: The eBike may limit or disable normal electrical operation to protect the battery.

What Does Bafang Error Code 46 Mean?

Bafang Error Code 46 means that the battery temperature is too low for normal operation.

The battery's temperature monitoring system detects the internal temperature of the battery pack. When the battery becomes excessively cold, the system may activate a low-temperature protection function.

This protection is particularly important for lithium-ion batteries because charging or operating them under extreme cold conditions can reduce performance and, especially during charging, potentially damage the cells.

Why Does Bafang Error Code 46 Happen?

Common causes include:

• Freezing weather: The eBike is being used or charged in very cold conditions, particularly around or below 0°C / 32°F.
• Cold storage: The battery has been left outside, in an unheated garage, shed, vehicle, or other cold environment for an extended period.
• Cold-soaked battery: Even if the outdoor temperature has started rising, the inside of the battery may still be extremely cold.
• Temperature sensor problem: If Error Code 46 remains after the battery has warmed to room temperature, the internal temperature sensor or related battery electronics may have a fault.

Common Symptoms

When Error Code 46 occurs, you may notice:

• The display shows 46.
• The motor does not work or assistance is restricted.
• Pedal assistance may be unavailable.
• The error appears after the eBike has been stored outside in cold weather.
• The battery may not charge normally.
• The error disappears after the battery warms up.

How to Fix Bafang Error Code 46

Step 1: Move the Battery to a Warmer Environment

Turn off the eBike and bring the battery indoors.

Allow it to warm naturally to normal room temperature. A practical target is approximately 68–72°F (20–22°C).

If the battery has been exposed to freezing temperatures for several hours, allow enough time for the entire battery pack, not just its outer casing, to warm up.

Do not use a hair dryer, heat gun, heater, open flame, or other high-temperature heat source to warm the battery rapidly.

Step 2: Restart the eBike

Once the battery has warmed:

1. Make sure the eBike system is turned off.
2. Reinstall the battery securely.
3. Check that the battery terminals are clean and dry.
4. Turn the system back on.
5. Check whether Error Code 46 has disappeared.

If the error was caused simply by cold weather, the system may return to normal once the battery reaches an acceptable operating temperature.

Step 3: Do Not Charge a Frozen Battery

Avoid attempting to force-charge a lithium-ion battery while it is extremely cold or frozen.

Instead, bring the battery indoors and allow it to warm naturally before charging.

Important: A battery that feels cold on the outside may still be colder internally. Give a cold-soaked battery sufficient time to reach a safe charging temperature.

Step 4: Check the Battery Connections

If Error Code 46 remains after the battery has warmed up, inspect the accessible battery connections.

Check for:

• Dirt on the battery terminals
• Moisture or condensation
• Corrosion
• Loose connections
• Damaged communication pins
• Poor battery seating

Clean and dry accessible connections where necessary and reinstall the battery securely.

What If Error Code 46 Remains After the Battery Warms Up?

If the battery has reached normal room temperature but Error Code 46 remains active, the problem may no longer be environmental.

Possible causes include a faulty internal temperature sensor, battery electronics, or a related communication problem.

At this point, have the battery professionally diagnosed rather than opening the battery pack yourself.

Error Code 45 vs. Error Code 46

These two Bafang codes indicate opposite battery-temperature conditions:

Error Code	Meaning	First Action
45	Battery temperature is too high	Turn off the system and allow the battery to cool naturally.
46	Battery temperature is too low	Move the battery to a warmer environment and allow it to warm naturally.

Quick Troubleshooting Summary

Error 46 → Battery temperature is too low → Turn off the eBike → Bring the battery indoors → Allow it to warm naturally to room temperature → Do not charge it while frozen → Reinstall the battery → Restart the system → If Error Code 46 remains after the battery is fully warmed, have the battery and its temperature sensor professionally inspected.

Error Code 47: Battery SOC Is Too High

Error Code: 47
Cause: The battery SOC is too high.
Result: The display shows Error Code 47, and the motor cannot operate.

What Does Bafang Error Code 47 Mean?

Bafang Error Code 47 indicates that the system has detected that the battery's State of Charge (SOC) is too high.

SOC, or State of Charge, represents the battery's current charge level. The Battery Management System (BMS) monitors this information and communicates the battery's SOC to the controller.

The BMS is installed inside the battery pack.

After the eBike system is turned on, diagnostics run continuously. If an excessively high SOC condition is detected, Error Code 47 appears and the motor is disabled.

Common Symptoms

When Error Code 47 occurs, you may notice:

• The display shows 47.
• The motor cannot operate.
• Pedal assistance is unavailable.
• The throttle, if equipped, cannot power the motor.
• The battery may appear fully charged.
• Restarting the eBike may not clear the error.

How to Fix Bafang Error Code 47

Step 1: Replace the Battery

According to Bafang's troubleshooting procedure, the recommended action for Error Code 47 is to replace the battery.

Diagnosis	Solution
Error Code 47 is displayed and the motor cannot operate.	Replace the battery.
A replacement battery has been installed.	Continue to Step 2 and verify that the error has cleared.

Because the BMS is installed inside the battery pack, the supplied Bafang troubleshooting procedure does not provide a user-level repair procedure for the BMS itself.

Safety Warning: Do not open the lithium-ion battery pack or attempt to modify the BMS or individual cells yourself. Internal battery servicing should be performed by a qualified battery technician.

Step 2: Clear Error Code 47

After replacing the battery:

1. Connect all components correctly.
2. Make sure the battery is properly installed.
3. Turn on the eBike system.
4. Check the display.
5. Confirm that motor operation has returned to normal.

Result	Next Action
Error Code 47 is inactive.	The repair is complete.
Error Code 47 remains active.	Return to Step 1 and recheck the battery. If all troubleshooting steps have been completed and checked again, contact Bafang.

What Is the BMS's Role in Error Code 47?

The Battery Management System (BMS) communicates the battery's SOC information to the controller.

Therefore, Error Code 47 is associated with the battery and its reported State of Charge rather than an external component such as the speed sensor, brake sensor, or display.

For this reason, Bafang's specified troubleshooting action is battery replacement.

Quick Troubleshooting Summary

Error 47 → Battery SOC is too high → Motor cannot operate → Replace the battery → Connect all components → Turn on the eBike → Check the display → If Error Code 47 is inactive, repair is complete → If Error Code 47 remains active, repeat the battery check or contact Bafang.

Error Code 48: Battery SOC Is Too Low

Error Code: 48
Cause: The battery SOC is too low.
Result: The display shows Error Code 48, and the motor cannot operate.

What Does Bafang Error Code 48 Mean?

Bafang Error Code 48 indicates that the system has detected that the battery's State of Charge (SOC) is too low.

SOC, or State of Charge, represents the battery's current charge level. The Battery Management System (BMS) communicates the battery's SOC information to the controller.

The BMS is installed inside the battery pack.

After the eBike system is turned on, diagnostics run continuously. If the system detects an excessively low SOC condition, Error Code 48 appears and the motor cannot operate.

Common Symptoms

When Error Code 48 occurs, you may notice:

• The display shows 48.
• The motor does not work.
• Pedal assistance is unavailable.
• The throttle, if equipped, cannot operate the motor.
• The system reports a battery SOC-related fault.
• Restarting the eBike does not necessarily clear the error.

How to Fix Bafang Error Code 48

Step 1: Replace the Battery

According to the supplied Bafang troubleshooting procedure, the specified solution for Error Code 48 is to replace the battery.

Diagnosis	Solution
Error Code 48 is displayed and the motor cannot operate.	Replace the battery.
The battery has been replaced.	Continue to Step 2 and verify that the error has cleared.

Although "SOC too low" may sound like a simple low-charge warning, the supplied Bafang troubleshooting procedure specifically instructs technicians to replace the battery. It does not provide charging the battery as a troubleshooting step for this particular error code.

Because the BMS is located inside the battery pack, the supplied procedure also does not provide instructions for repairing the BMS separately.

Safety Warning: Do not open the lithium-ion battery pack or attempt to repair its BMS or cells yourself. Internal battery servicing should be performed by an appropriately qualified technician.

Step 2: Clear Error Code 48

After replacing the battery:

1. Connect all components correctly.
2. Make sure the battery is securely installed.
3. Turn on the eBike system.
4. Check the display.
5. Confirm that the motor operates normally.

Result	Next Action
Error Code 48 is inactive.	The repair is complete.
Error Code 48 remains active.	Return to Step 1 and recheck the battery. If all troubleshooting steps have been completed and checked again, contact Bafang.

Error Code 47 vs. Error Code 48

These two Bafang codes are both related to the battery's State of Charge:

Error Code	Meaning	Bafang-Specified Solution
47	Battery SOC is too high.	Replace the battery.
48	Battery SOC is too low.	Replace the battery.

In simple terms, Error 47 indicates an abnormally high SOC condition, while Error 48 indicates an abnormally low SOC condition. For both faults, the supplied troubleshooting procedure specifies battery replacement.

Quick Troubleshooting Summary

Error 48 → Battery SOC is too low → Motor cannot operate → Replace the battery → Connect all components → Turn on the eBike → Check the display → If Error Code 48 is inactive, repair is complete → If Error Code 48 remains active, repeat the battery check or contact Bafang.

Error Code CF01: The Mass Code

Error Code: CF01
Cause: The mass code.
Result: The display cannot work normally.

What Does Bafang Error Code CF01 Mean?

Bafang Error Code CF01, described in the supplied troubleshooting information as “The mass code,” indicates a fault that prevents the display from operating normally.

The troubleshooting procedure focuses on two components:

• The display
• The controller

The recommended diagnostic approach is to test the display first. If replacing the display does not solve the problem, the controller should be tested next.

Common Symptoms

When CF01 occurs, you may notice:

• The display does not work normally.
• Replacing the display may resolve the problem.
• If a replacement display does not work, the controller may be responsible.
• If replacing both components does not restore normal operation, Bafang recommends contacting its service team.

How to Fix Bafang Error Code CF01

Step 1: Check the Display

Replace the existing display with a known-good compatible display to determine whether the original display is causing the problem.

Test Result	Solution
The new display works normally.	The original display is the problem. Repair is complete.
The new display still does not work normally.	Continue to Step 2.

This test helps isolate the display before moving on to the controller.

Step 2: Replace the Controller

If installing a new display does not solve the problem, replace the controller with a compatible unit and test the system again.

Test Result	Solution
The display works normally after replacing the controller.	The controller was the problem. Repair is complete.
The display still does not work.	Contact Bafang for further diagnosis.

What Should You Replace First?

For CF01, follow the troubleshooting sequence in the supplied Bafang information rather than replacing multiple components at once:

Display first → Controller second → Contact Bafang if the problem remains.

This sequence makes it easier to identify which component is actually responsible for the fault.

Quick Troubleshooting Summary

CF01 → Display cannot work normally → Test with a new display → If the new display works, repair is complete → If it does not work, replace/test the controller → If the display then works normally, repair is complete → If it still does not work, contact Bafang.

Error Code CF02: Cannot Power On the Display

Error Code: CF02
Cause: Cannot power on the display.
Result: The display cannot be powered on.

What Does Bafang Error Code CF02 Mean?

Bafang Error Code CF02 means that the eBike's display cannot power on.

Based on the supplied Bafang troubleshooting procedure, the first component to check is the display itself. Testing the system with a known-good replacement display helps determine whether the original display is faulty.

Common Symptoms

When CF02 occurs, you may notice:

• The display does not turn on.
• The screen remains blank.
• Pressing the display's power button produces no response.
• Repeated attempts to turn on the display do not work.
• Installing a replacement display may restore normal operation.

How to Fix Bafang Error Code CF02

Step 1: Check the Display

Replace the existing display with a known-good compatible display to determine whether the original display is causing the problem.

Test Result	Solution
The new display works normally.	The original display is faulty. Repair is complete.
The new display does not work.	Continue to Step 2.

When testing with another display, make sure the replacement is compatible with the specific Bafang drive system.

What If a New Display Does Not Work?

The supplied troubleshooting information ends with:

“The new display doesn't work. Go to Step 2.”

However, Step 2 is not included in the material provided here. Therefore, the next repair action cannot be determined from this source alone.

Rather than assuming that the controller, wiring, battery, or another component should be replaced, continue with the next step from the Bafang service documentation for your specific system.

Quick Troubleshooting Summary

CF02 → Display cannot power on → Test with a known-good compatible display → If the new display works, the original display is faulty and the repair is complete → If the new display also does not work, continue to Step 2 of the applicable Bafang troubleshooting procedure.

Error Code CF03: Runaway Phenomenon

Error Code: CF03
Cause: Runaway phenomenon.
Result: The motor runs at high speed as soon as the system is turned on.

What Does Bafang Error Code CF03 Mean?

Bafang Error Code CF03 describes a runaway phenomenon, where the motor immediately operates at high speed when the eBike system is switched on.

This is different from a typical situation where the motor fails to start. With CF03, the problem is that the motor activates unexpectedly and runs at high speed without normal rider input.

According to the supplied Bafang troubleshooting procedure, the two components to test are:

• The controller
• The sensor

The controller should be replaced/tested first. If the problem remains, the sensor should be replaced/tested next.

Common Symptoms

The primary symptom of CF03 is:

• The motor runs at high speed immediately after the system is powered on.

Because unexpected motor activation can cause the bicycle to move suddenly, do not continue normal riding until the problem has been corrected.

How to Fix Bafang Error Code CF03

Step 1: Replace the Controller

Replace the existing controller with a known-good compatible controller to determine whether the controller is responsible for the runaway condition.

Test Result	Solution
The problem is solved.	The controller was the problem. Repair is complete.
The error still occurs.	Continue to Step 2.

Make sure the replacement controller is compatible with the specific Bafang system before performing the test.

Step 2: Replace the Sensor

If replacing the controller does not solve CF03, replace the sensor with a known-good compatible unit and test the system again.

Test Result	Solution
The problem is solved.	The sensor was the problem. Repair is complete.
The error still occurs.	Contact Bafang.

Safety Precautions When Testing CF03

Because CF03 can cause the motor to run at high speed immediately after startup, use extra caution during troubleshooting.

Before powering the system on, keep the drive wheel safely off the ground or otherwise prevent the bicycle from moving unexpectedly. Keep hands, clothing, tools, and other objects away from the wheel and drivetrain.

Do not ride the eBike while the runaway condition is still present.

What Should You Replace First?

Follow the troubleshooting sequence provided in the Bafang information:

Controller first → Sensor second → Contact Bafang if the problem remains.

Avoid replacing both components at the same time, because testing them individually makes it easier to identify the source of the problem.

Quick Troubleshooting Summary

CF03 → Motor runs at high speed immediately after startup → Replace/test the controller → If the problem is solved, repair is complete → If the problem remains, replace/test the sensor → If the problem is solved, repair is complete → If the runaway condition still occurs, contact Bafang.

Error Code CF04: E-Brake Cannot Work

Error Code: CF04
Cause: The E-brake does not work.
Result: The E-brake cannot operate.

What Does Bafang Error Code CF04 Mean?

Bafang Error Code CF04 indicates that the eBike's E-brake is not working correctly.

According to the supplied Bafang troubleshooting procedure, diagnosis focuses on two components:

• The E-brake
• The controller

The E-brake should be replaced and tested first. If that does not solve the problem, the controller should be replaced and tested.

Common Symptoms

When CF04 occurs, you may notice:

• The E-brake does not work.
• The electronic brake function does not respond normally.
• Replacing the E-brake may solve the problem.
• If the problem remains with a new E-brake, the controller may be responsible.

How to Fix Bafang Error Code CF04

Step 1: Replace the E-Brake

Replace the existing E-brake with a new compatible E-brake to determine whether the brake itself is causing the fault.

Test Result	Solution
The problem is solved.	The E-brake was the problem. Repair is complete.
The error still occurs.	Continue to Step 2.

This is the first diagnostic step specified in the supplied Bafang troubleshooting procedure.

Step 2: Replace the Controller

If replacing the E-brake does not solve the problem, replace the controller with a new compatible controller and test the E-brake again.

Test Result	Solution
The problem is solved.	The controller was the problem. Repair is complete.
The error still occurs.	Contact Bafang.

What Should You Replace First?

Follow the troubleshooting sequence provided by Bafang:

E-brake first → Controller second → Contact Bafang if the problem remains.

Testing the components in this order makes it easier to identify whether the fault originates from the E-brake or the controller.

CF04 vs. Error Code 33

CF04 and Error Code 33 are both related to the electronic braking system, but the supplied troubleshooting procedures describe them differently:

Code	Problem
33	Brake detection circuit fault
CF04	E-brake does not work

For CF04, the supplied procedure specifically instructs you to replace/test the E-brake first and then replace/test the controller if necessary.

Quick Troubleshooting Summary

CF04 → E-brake cannot work → Replace/test the E-brake → If the problem is solved, repair is complete → If the error remains, replace/test the controller → If the problem is solved, repair is complete → If CF04 still occurs, contact Bafang.

Error Code CF05: The Light Cannot Work

Error Code: CF05
Cause: The light cannot work.
Result: The light cannot operate normally.

What Does Bafang Error Code CF05 Mean?

Bafang Error Code CF05 indicates that the eBike's light is not operating normally.

According to the supplied Bafang troubleshooting information, the first diagnostic step is to replace the light with a new one and check whether this resolves the problem.

Common Symptoms

When CF05 occurs, you may notice:

• The eBike light does not turn on.
• The light does not operate normally.
• Replacing the light may restore normal operation.
• The problem remains even after installing a new light.

How to Fix Bafang Error Code CF05

Step 1: Replace the Light

Replace the existing light with a new compatible light to determine whether the light itself is causing the problem.

Test Result	Solution
The problem is solved.	The original light was the problem. Repair is complete.
The error still occurs.	Continue to Step 2.

Make sure the replacement light is compatible with the specific Bafang system before testing it.

What If a New Light Does Not Work?

The supplied troubleshooting information ends with:

“Error still happen. Go to step 2.”

However, Step 2 is not included in the information provided here. Therefore, the next troubleshooting action cannot be determined from this source alone.

Rather than assuming that the controller, wiring, display, or another component should be replaced, continue with Step 2 from the applicable Bafang service documentation.

Quick Troubleshooting Summary

CF05 → Light cannot work normally → Replace/test the light → If the new light works, repair is complete → If the problem remains, continue to Step 2 of the applicable Bafang troubleshooting procedure.

Error Code CF06: 6km/h Walk Assistance Does Not Work

Error Code: CF06
Cause: The 6km function does not work.
Result: Walk assistance cannot operate.

What Does Bafang Error Code CF06 Mean?

Bafang Error Code CF06 indicates that the eBike's 6km walk-assistance function is not working.

The troubleshooting procedure provided for CF06 focuses on three components:

• The controller
• The display
• The motor

The controller should be replaced and tested first. If that does not solve the problem, test the display next, followed by the motor.

Common Symptoms

When CF06 occurs, you may notice:

• The 6km function does not work.
• Walk assistance cannot be activated.
• The bike does not provide walk-assist power.
• Replacing the controller may solve the problem.
• If the controller is not responsible, the display or motor may be faulty.

How to Fix Bafang Error Code CF06

Step 1: Replace the Controller

Replace the existing controller with a new compatible controller to determine whether the controller is causing the problem.

Test Result	Solution
The problem is solved.	The controller was the problem. Repair is complete.
The error still occurs.	Continue to Step 2.

Step 2: Replace the Display

If replacing the controller does not restore the 6km walk-assistance function, replace the display with a new compatible display.

Test Result	Solution
The problem is solved.	The display was the problem. Repair is complete.
The error still occurs.	Continue to Step 3.

Step 3: Replace the Motor

If replacing both the controller and display does not solve CF06, replace the motor with a new compatible motor and test the walk-assistance function again.

Test Result	Solution
The problem is solved.	The motor was the problem. Repair is complete.
The error still occurs.	Contact Bafang.

What Should You Replace First?

Follow the troubleshooting sequence provided by Bafang:

Controller → Display → Motor → Contact Bafang

Testing the components in this order makes it easier to determine which part is responsible for the walk-assistance failure.

Quick Troubleshooting Summary

CF06 → 6km walk assistance does not work → Replace/test the controller → If the problem remains, replace/test the display → If it still remains, replace/test the motor → If CF06 persists after all three steps, contact Bafang.

Error Code CF07: The Throttle Does Not Work

Error Code: CF07
Cause: The throttle does not work.
Result: The system cannot operate normally.

What Does Bafang Error Code CF07 Mean?

Bafang Error Code CF07 indicates that the eBike's throttle is not working, preventing the system from operating normally.

According to the supplied Bafang troubleshooting procedure, diagnosis focuses on two components:

• The throttle
• The controller

The recommended troubleshooting sequence is to replace and test the throttle first. If the problem remains, replace and test the controller.

Common Symptoms

When CF07 occurs, you may notice:

• The throttle does not respond.
• Pressing or twisting the throttle does not activate the motor.
• The system does not operate normally.
• Replacing the throttle may solve the problem.
• If a new throttle does not solve the problem, the controller may be responsible.

How to Fix Bafang Error Code CF07

Step 1: Replace the Throttle

Replace the existing throttle with a new compatible throttle to determine whether the throttle itself is causing the problem.

Test Result	Solution
The problem is solved.	The throttle was the problem. Repair is complete.
The error still occurs.	Continue to Step 2.

This is the first troubleshooting step specified in the supplied Bafang procedure.

Step 2: Replace the Controller

If replacing the throttle does not solve CF07, replace the controller with a new compatible controller and test the system again.

Test Result	Solution
The problem is solved.	The controller was the problem. Repair is complete.
The error still occurs.	Contact Bafang.

What Should You Replace First?

Follow the troubleshooting sequence provided by Bafang:

Throttle → Controller → Contact Bafang

Testing the throttle first helps determine whether the fault is simply with the throttle itself before replacing the controller.

CF07 vs. Error Code 04

Both codes involve the throttle, but they describe different problems:

Code	Problem
04	The throttle has not returned to its correct position.
CF07	The throttle does not work.

For CF07, the supplied Bafang troubleshooting procedure specifically recommends replacing/testing the throttle first and then replacing/testing the controller if the problem remains.

Quick Troubleshooting Summary

CF07 → Throttle does not work → Replace/test the throttle → If the problem is solved, repair is complete → If the problem remains, replace/test the controller → If the controller replacement solves the problem, repair is complete → If CF07 still occurs, contact Bafang.

Error Code CF08: The Cruising Range Is Short

Error Code: CF08
Cause: The NEDC is abnormal.
Result: The cruising range is short.

What Does Bafang Error Code CF08 Mean?

Bafang Error Code CF08 indicates an abnormal NEDC condition associated with short cruising range.

In practical terms, the eBike is not achieving the expected riding range. According to the supplied Bafang troubleshooting procedure, diagnosis focuses on two components:

• The battery
• The controller

The battery should be replaced and tested first. If the range problem remains, the controller should be replaced and tested next.

Common Symptoms

When CF08 occurs, you may notice:

• The eBike's cruising range is unusually short.
• The battery appears to discharge faster than expected.
• The bike travels significantly less distance than expected before requiring another charge.
• Replacing the battery may restore normal range.
• If a replacement battery does not solve the problem, the controller may be responsible.

How to Fix Bafang Error Code CF08

Step 1: Replace the Battery

Replace the existing battery with a new compatible battery to determine whether the battery is causing the short cruising range.

Test Result	Solution
The problem is solved.	The battery was the problem. Repair is complete.
The error still occurs.	Continue to Step 2.

According to the supplied Bafang procedure, the battery is the first component to test for CF08.

When testing with another battery, make sure it is compatible with the specific Bafang system.

Step 2: Replace the Controller

If replacing the battery does not solve the short-range problem, replace the controller with a new compatible controller and test the eBike again.

Test Result	Solution
The problem is solved.	The controller was the problem. Repair is complete.
The error still occurs.	Contact Bafang.

What Should You Replace First?

Follow the troubleshooting sequence provided by Bafang:

Battery → Controller → Contact Bafang

Testing the battery first helps determine whether the short cruising range is caused by the battery before replacing the controller.

CF08 vs. a Normal Reduction in eBike Range

CF08 specifically refers to the “NEDC is abnormal / cruising range is short” condition in the supplied Bafang troubleshooting procedure.

A short real-world range can have many possible causes, but the supplied procedure does not provide troubleshooting steps for factors such as tire pressure, rider weight, hills, weather, assist level, or riding speed.

For CF08 specifically, Bafang's provided diagnostic sequence is simply:

1. Test with a replacement battery.
2. If the problem remains, test with a replacement controller.
3. If the problem still remains, contact Bafang.

Quick Troubleshooting Summary

CF08 → Cruising range is short → Replace/test the battery → If the problem is solved, repair is complete → If the problem remains, replace/test the controller → If the problem is solved, repair is complete → If the cruising range is still abnormally short, contact Bafang.

Error Code CF09: Issues on Display

Error Code: CF09
Cause: Issue with the display.
Result: The display cannot work normally.

What Does Bafang Error Code CF09 Mean?

Bafang Error Code CF09 indicates a problem with the eBike display that prevents it from operating normally.

Unlike some Bafang error codes that require several diagnostic steps, the supplied troubleshooting procedure recommends direct display replacement when certain physical or functional problems are present.

When Should You Replace the Display?

According to the supplied Bafang troubleshooting information, the display should be replaced directly if any of the following problems occur:

• A. Water inside the display
• B. Display buttons do not work
• C. Display cable is broken
• D. Screen is broken
• E. Display holder is broken
• F. Screw is broken
• G. Black screen

If your Bafang display has any of these symptoms, the specified procedure does not require additional component-level repair before testing a replacement display.

How to Fix Bafang Error Code CF09

Step 1: Replace the Display

Replace the faulty display with a new compatible display.

After installation, turn on the eBike and check whether the display operates normally.

Test Result	Solution
The problem is solved.	Repair is complete.
The problem still occurs.	Contact Bafang.

Make sure the replacement display is compatible with your specific Bafang system before installation.

What Should You Check Before Replacing the Display?

The supplied CF09 procedure specifically identifies visible or functional display failures as reasons for direct replacement.

For example, if the screen is physically broken, water has entered the display, the display cable is broken, or the display remains black, replacement is the specified troubleshooting action.

Similarly, a broken button, holder, or screw is included in the supplied list of conditions for replacing the display.

CF09 vs. CF02

CF09 and CF02 can both involve display problems, but the supplied troubleshooting information describes them differently:

Code	Problem
CF02	Cannot power on the display
CF09	Display cannot work normally, including water ingress, broken buttons/cable/screen/holder/screw, or a black screen

For CF09, the specified procedure is straightforward: replace the display and test the system.

Quick Troubleshooting Summary

CF09 → Display does not work normally → Check for water ingress, failed buttons, broken cable, broken screen, broken holder, broken screw, or black screen → Replace the display → Test the system → If the problem is solved, repair is complete → If the problem remains, contact Bafang.