U0073critical severityNetwork
Control Module Communication Bus A Off
on 2000 BMW M5 4.9L V8 S62 · RWD
What this code means
CAN bus A is not communicating. Complete loss of communication on the primary bus.
Symptoms
- Multiple systems down
- Multiple warning lights
- Vehicle may not start
- No scan tool communication
Common causes
- CAN bus wiring shorted or open
- Termination resistor failure
- Module failure shorting the bus
- Major wiring harness damage
Diagnostic steps
- Check CAN bus voltage levels
- Measure bus resistance
- Isolate bus segments
- Check for physical damage to wiring
Repair notes
Major network failure. Systematic diagnosis required.
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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