Over current of motor

Stop riding Last verified: pending review Reviewed by: editorial team

Quick answer

Error code 12 signifies a current sensor abnormality within the controller. This issue typically arises from problems with the shunt in the controller, which cannot be replaced. A firmware update may help, but if the error persists, the controller will need to be replaced.

Stop riding Often DIY-friendly Beginner (15–30 min)

Does this apply to your bike?

H700 · Bafang · Common displays: DP E171

Heads-up: the same number can mean different things on other systems — always check your drive system first. Browse all drive systems →

What you’ll notice

The display shows error code 12, and the bike may not operate correctly.

Likely causes, ranked

Start at #1 — causes are ordered by how often they turn out to be the problem.

#1 Current sensor malfunction

How to check: Inspect the controller for signs of damage or overheating.

#2 Firmware issues

How to check: Check if a firmware update is available for the controller.

Troubleshooting steps

Inspect the controller

easy

Check for any visible damage or overheating signs on the controller.

If it passes →Proceed to check firmware.

If it fails →Replace the controller.
Check for firmware updates

easy

Verify if there is a firmware update available for the controller and install it.

If it passes →Test the system to see if the error persists.

If it fails →Replace the controller.

When to stop and get professional help

If you notice any signs of burning, melting, or other severe damage.

Never open, puncture, or disassemble the battery pack, and never bypass the BMS. See our safety guide.

More codes for H700

09 · Fault with motor phase winding 10 · Overtemperature of motor 11 · Motor temperature sensor fault 13 · Battery temperature sensor fault 14 · Overtemperature of controller 15 · Controller temperature sensor fault

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Sources & verification

Last verified: pending review Reviewed by: editorial team

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