U0026high severityNetwork
Control Module Communication Bus B Low
on 2011 Audi Q7 3.0L Supercharged V6 · AWD
What this code means
The B communication bus voltage is reading too low, which disrupts data sharing between modules. This can cause multiple systems to lose communication with each other.
Symptoms
- Warning lights on dash
- Multiple systems malfunctioning
- Intermittent module dropout
Common causes
- Shorted bus B wiring to ground
- Corroded or loose connectors
- Failed control module on bus B
- Damaged wiring harness
Diagnostic steps
- Scan all modules for stored codes
- Inspect bus B wiring for shorts
- Measure bus B voltage with scope
- Isolate modules to find fault source
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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