Over current of the controller

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

Quick answer

Error code 27 signifies that the controller has detected an overcurrent condition. This typically means that the current flowing through the controller exceeds safe operational limits, which can lead to potential damage if not addressed. It is advisable to consult a professional for further diagnosis and repair.

Stop riding Often DIY-friendly Intermediate (30–60 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 27, and the motor may not function properly.

Likely causes, ranked

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

#1 Excessive load on the controller

How to check: Inspect the load conditions and ensure they are within the controller's specifications.

#2 Faulty wiring or connections

How to check: Check all wiring and connectors for damage or loose connections.

#3 Controller malfunction

How to check: Test the controller with diagnostic tools to confirm its operational status.

Troubleshooting steps

Check load conditions

easy

Ensure that the load on the controller is within the specified limits.

If it passes →Proceed to check wiring.

If it fails →Reduce load or consult a professional.
Inspect wiring and connections

easy

Look for any signs of damage or loose connections in the wiring.

If it passes →Proceed to test the controller.

If it fails →Repair or replace damaged wiring.
Test the controller

Tools: Diagnostic tool intermediate

Use diagnostic tools to check the controller's functionality.

If it passes →If the controller is functional, further investigation may be needed.

If it fails →Replace the controller.

When to stop and get professional help

If the controller shows persistent errors after checks, consult a professional.

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

More codes for H700

21 · Speed sensor fault 25 · Torque signal fault 26 · Torque sensor speed signal fault 30 · Communication failed 33 · Brake detection circuit is fault 35 · Detection circuit for 15V has an error

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Sources & verification

Last verified: pending review Reviewed by: editorial team

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