U0424low severityNetwork
Invalid Data Received From HVAC Control Module
on 2009 Audi A3 2.0L TDI · FWD
What this code means
The network is receiving corrupted data from the HVAC control module. This can cause heating and air conditioning to work improperly.
Symptoms
- HVAC not responding
- Incorrect temperature output
- Climate display errors
Common causes
- Faulty HVAC 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 HVAC module
- Inspect data bus wiring and connectors
- Review HVAC 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
Engine Control Module (ECM) - no communications
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