U0321moderate severityNetwork
Software Incompatibility With Vehicle Security Control Module
on 2003 BMW M5 4.9L V8 S62 · RWD
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
CC-ID-181
System Check Failed
CC-ID-207
Central Electronics Failure, Stop Vehicle
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High