U0401moderate severityNetwork
Invalid Data Received from ECM/PCM
on 2005 Audi A6 3.2L V6 · AWD
What this code means
The data received from the PCM is invalid or corrupted.
Symptoms
- Various warning lights
- Erratic system behavior
Common causes
- PCM software issue
- CAN bus noise
- PCM failure
- Wiring interference
Diagnostic steps
- Update PCM software
- Check for TSBs
- Test CAN bus signal quality
- Check for electromagnetic interference
Repair notes
Reprogram PCM. Check CAN bus.
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Other Network codes on this vehicle
01314
Engine Control Module (ECM) - no communications
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together