U0259low severityNetwork
Lost Communication With Fuel Fired Heater Control Module
on 2009 Audi A3 2.0L TDI · FWD
What this code means
The vehicle's network has lost contact with the fuel fired heater control module. This is usually a wiring or module fault affecting the auxiliary heater.
Symptoms
- No or weak cabin heat
- Warning light on dash
- Auxiliary heater inoperative
Common causes
- Faulty wiring or connector to heater module
- Failed fuel fired heater control module
- Blown fuse or power supply issue
- Corrupted CAN bus network
Diagnostic steps
- Scan for related communication codes
- Check power and ground at heater module
- Inspect wiring and connectors for damage
- Test CAN bus continuity to module
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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