U0016
Medium Speed CAN Communication Bus Off
A controller on the medium-speed comfort bus has shut its transceiver off after too many consecutive transmit errors. Comfort and body functions stop responding until the bus recovers or is repaired.
- 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.
- Wiring short forces bus-off stateCommon
- One failing node corrupts trafficPossible
- Gateway module routing CAN messages incorrectlyLess likely
Parts involved
- Body Control Module
- CAN Bus Wiring
U0016 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.