U0321moderate severityNetwork
Software Incompatibility With Vehicle Security Control Module
on 2000 Audi A6 2.7L Turbo V6 · AWD
What this code means
The security control module software does not match what other modules expect. This can prevent proper vehicle security and immobilizer operation.
Symptoms
- Vehicle won't start
- Security light illuminated
- Communication faults with modules
Common causes
- Incorrect module software version
- Incomplete module programming
- Mismatched replacement module
- Failed software update
Diagnostic steps
- Verify module software and part numbers
- Compare against factory calibration data
- Reflash module with correct software
- Clear codes and retest security functions
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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