U0039low severityNetwork
LIN Bus A (-) Open
on 2005 BMW 330i 3.0L I6 M54 · RWD
What this code means
The LIN bus A ground reference is open, preventing proper LIN communication.
Symptoms
- LIN slave devices not responding
- Erratic LIN device behavior
Common causes
- LIN ground wire open
- Corroded ground connection
- Broken ground splice
Diagnostic steps
- Check LIN ground continuity
- Inspect ground connection points
- Test for proper ground at LIN devices
Repair notes
Repair the open ground on the LIN bus circuit.
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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