OBD-II code · Network
U0080 Vehicle Communication Bus B (+) High
The plus line of bus B is shorted to battery voltage. The bus stops carrying valid frames. A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.
Is it safe to drive with U0080?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyBus-B plus shorted to battery
- 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
- 0.8–5 h
- Emissions test
- Usually unaffected
- Parts involved
- Can High Wire
Related codes
- U0032Vehicle Communication Bus A (+) High
- U0041Vehicle Communication Bus B (+) High
- U0059Vehicle Communication Bus D (+) High
- U0068Vehicle Communication Bus E (+) High
- U008DVehicle Communication Bus G (+) High
- U0096Vehicle Communication Bus H (+) High
- U007DControl Module Communication Bus K Off
- U007EControl Module Communication Bus L Off
- U007FControl Module Communication Bus M Off
- U0081Vehicle Communication Bus F Performance
- U0082Vehicle Communication Bus F + Open
- U0083Vehicle Communication Bus F + Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.