U0056low severityNetwork
LIN Bus B Communication Performance
on 2019 Audi A6 2.0L Turbo I4 · AWD
What this code means
Communication on LIN bus B is degraded or intermittent.
Symptoms
- Specific LIN B devices intermittent
- HVAC blend door actuator issues
- Seat heater communication errors
Common causes
- LIN bus B wiring degradation
- LIN slave device fault on bus B
- High resistance in LIN B circuit
Diagnostic steps
- Check LIN bus B voltage levels
- Test LIN B wiring resistance
- Inspect LIN B device connections
- Test individual LIN B slave devices
Repair notes
Check LIN bus B wiring and slave device connections.
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00003
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U0001
High Speed CAN Communication Bus