OBD-II code · Network
U01BB Lost Communication With Battery Charger Control Module B
ECU lost communication with battery charger control module B (on-board charger for HV battery on plug-in hybrids/EVs).
Is it safe to drive with U01BB?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
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
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–8 h
- Emissions test
- Usually unaffected
- Parts involved
- Battery Charger Module B, Can Bus
Related codes
- U019BLost Communication With Battery Charger Control Module A
- U027ALost Communication With Battery Charger Control Module C
- U027BLost Communication With Battery Charger Control Module D
- U01B8Lost Communication With Switch Input Module B
- U01B9Lost Communication With Switch Input Module C
- U01BALost Communication With Park Lock/Pawl Control Module
- U01BCLost Communication With Charge Air Cooler Coolant Pump B
- U01BDLost Communication With DC/DC Converter Control Module C
- U01BELost Communication with Drive Motor A Clutch Actuator
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.