U01BF

Q: Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

Lost Communication with Battery Management Control Module

High severity

ECU lost CAN communication with the main battery management control module (BMS) — central HV battery controller.

Common causes

Module unpowered or HV interlock open
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $440-4400
Gateway module routing CAN messages incorrectly
Less common, but worth ruling out after the more likely causes.
low
Typical part cost: $440-4400
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does U01BF mean?

U01BF means "Lost Communication with Battery Management Control Module". It is a generic OBD-II code that points to a fault in the network / communication.

What are the most common causes of U01BF?

module unpowered or hv interlock open; gateway module routing can messages incorrectly; can terminating resistor (120 ω) drifted out of spec — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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