U0108moderate severityNetwork
Lost Communication with Exhaust Gas Recirculation Module
on 2003 BMW 525iT E39 2.5L I6 M54 Touring · RWD
What this code means
Cannot communicate with the EGR system control module.
Symptoms
- Check Engine Light
- Increased NOx emissions
- EGR-related DTCs
- Poor fuel economy
- Rough idle
Common causes
- EGR module failure
- CAN bus wiring issue
- Fuse blown
- Connector corrosion
- Carbon buildup causing module damage
Diagnostic steps
- Check EGR module fuse
- Test power and ground
- Inspect CAN wiring
- Check connector condition
- Test EGR module directly
Repair notes
Check fuses and wiring. EGR modules on diesels are prone to carbon contamination.
Other Network codes on this 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
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus