U0425low severityNetwork
Invalid Data Received From Auxiliary Heater Control Module
on 2003 Audi A6 3.0L V6 · AWD
What this code means
The computer is getting bad data from the auxiliary heater control module. This can cause the auxiliary heater to malfunction or not run.
Symptoms
- Auxiliary heater not working
- Slow cabin warm-up
- Heater warning message
Common causes
- Faulty auxiliary heater control module
- Bus wiring or connector fault
- Corroded or loose connectors
- Software or programming error
Diagnostic steps
- Scan all modules for codes
- Check power and ground to auxiliary heater module
- Inspect data bus wiring and connectors
- Review heater module live data with scan tool
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Other Network codes on this vehicle
00003
Control Module - Defective
01304
Radio - No Communication
01312
Powertrain Data Bus - Defective
01314
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01315
Transmission Control Module (TCM) - No Communication
01316
ABS Control Module - No Communication
01317
Instrument Cluster Control Module (J285) - No Communication
01318
Immobilizer Control Module - No Communication
01321
Airbag Control Module - No Communication
U0001
High Speed CAN Communication Bus