U0270moderate severityNetwork
Lost Communication With Body Control Module 'B'
on 2009 Audi Q7 3.0L Supercharged V6 · AWD
What this code means
The module has lost communication with a secondary body control module over the data bus. This can disable various body electrical functions controlled by that module.
Symptoms
- Body electrical features inoperative
- Warning lights on dash
- Intermittent module functions
Common causes
- Faulty body control module 'B'
- Damaged CAN bus wiring
- Loss of power or ground to module
- Corroded connectors
Diagnostic steps
- Scan all modules for stored codes
- Check power and ground at the module
- Test CAN bus wiring continuity and resistance
- Inspect connectors for corrosion or damage
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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