U0039low severityNetwork
LIN Bus A (-) Open
on 2019 Audi A6 3.0L V6 TFSI · AWD
What this code means
The LIN bus A ground reference is open, preventing proper LIN communication.
Symptoms
- LIN slave devices not responding
- Erratic LIN device behavior
Common causes
- LIN ground wire open
- Corroded ground connection
- Broken ground splice
Diagnostic steps
- Check LIN ground continuity
- Inspect ground connection points
- Test for proper ground at LIN devices
Repair notes
Repair the open ground on the LIN bus circuit.
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