OBD-II code · Network
U012F Lost Communication With Generator B Control Module
Lost Communication With Generator B Control Module: the control module has detected this fault condition.
Is it safe to drive with U012F?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyModule unpowered
- Less likelyGateway module routing CAN messages incorrectly
- Less likelyCAN terminating resistor (120 Ω) drifted out of spec
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
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–5 h
- Emissions test
- Usually unaffected
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Generator B Module, Can Bus
Related codes
- U012DLost Communication With Generator A Control Module
- U012CLost Communication With Active Vibration Control Module
- U012ELost Communication With Camshaft Position Control Module
- U0130Lost Communication with Steering Effort Control Module B
- U0131Lost Communication with Power Steering Control Module
- U0132Lost Communication with Ride Level Control Module
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.