Network
generic / SAE
U0071
Vehicle Communication Bus A (+) Bus Off
The CAN controller for bus A has shut its plus driver after exceeding the SAE J2284 / ISO 11898 transmit error threshold. The node disconnects from the bus until error counters recover.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number– / 71
Possible causes
- Persistent short on the CAN-H wire high
- One module driving bus permanently dominant medium
- Gateway module routing CAN messages incorrectly low
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
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 80–800 €
- Estimated time: 1–6 h
- Component: can transceiver
- Component: can high wire
- MIL / check engine light
- limp mode possible
Sources
References
sae:J2012
iso:11898