Bafang error 11: Controller temperature sensor error
Bafang BBS01/BBS02/BBSHD, M-series mid-drives and hub motors (UART & CAN displays)Dealer neededRide with caution
The temperature sensor inside the controller is reading an impossible value (open or shorted). The controller can no longer protect itself against overheating and many firmware versions limit or block power. The bike may still work partly but shows the code at every start.
Likely causes
- Sensor or its solder joint failed on the controller board
- Water ingress corroding the sensor circuit
- Controller damaged by an earlier overheat event
- Firmware glitch after an update (rare)
How to fix Bafang error 11
- Power cycle once to rule out a glitch
- Check for moisture in the controller housing or connectors; dry thoroughly
- If you have a Bafang programming cable, check the firmware version and reflash if a known bug applies
- Replace the controller; the sensor is not serviceable at home
Go to a dealer if: Go to a shop when the code persists after a power cycle; the fix is a controller replacement.
Warranty: If the bike or kit is under warranty (usually 1-2 years via the seller), contact them before opening anything, as opened motors and controllers can void the claim.
Typical cost: Controller replacement EUR/USD 80-250 including fitting.
Warranty: If the bike or kit is under warranty (usually 1-2 years via the seller), contact them before opening anything, as opened motors and controllers can void the claim.
Typical cost: Controller replacement EUR/USD 80-250 including fitting.
Still stuck? Take a photo of the display and show it to a local e-bike workshop. Bring the bike's system name (e.g. Bosch Performance Line CX) and the exact code; that saves diagnostic time and money.
Frequently asked
Can I reset error 11?
Only a power cycle; if the sensor is dead the code returns immediately.
Can I keep riding?
Short rides at low assist are usually possible, but the controller can no longer protect itself from heat.
Warranty?
Yes, a failed internal sensor is a controller defect.
Related Bafang codes
Not an official Bafang document. Compiled from workshop experience and public service information; details can differ per system version and bike brand.