U0135
Lost Communication with Parking Brake Control Module
The vehicle network has lost the electric parking brake (EPB) controller. Auto-hold is disabled, the EPB warning lamp comes on. EPB cannot be released electrically.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Common causes
Ordered by how often each turns out to be the cause.
- EPB module unpoweredCommon
- CAN wiring to EPB damagedPossible
- Gateway module routing CAN messages incorrectlyLess likely
Parts involved
- Epb Module
- CAN Bus Wiring
U0135 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.