U0129critical severityNetwork
Lost Communication with Brake System Control Module
on 2019 Audi A6 3.0L Turbo V6 · AWD
What this code means
Cannot communicate with the general brake system control module.
Symptoms
- Brake warning light on
- ABS disabled
- Stability control off
- Brake system message displayed
Common causes
- Brake module failure
- CAN bus wiring damage
- Module power loss
- Fuse blown
- Water damage
Diagnostic steps
- Check brake system fuses
- Test module power and ground
- Check CAN wiring
- Inspect module for water damage
- Try direct module communication
Repair notes
Check fuses and power supply. Inspect for water damage near brake module location.
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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