U0055
NetworkModule Communicationhigh severityControl Module Communication Bus E Low
What U0055 Means
The voltage on communication bus E is lower than expected. This can interrupt data exchange between modules on that circuit.
Symptoms
- Dash warning lights
- Module functions lost
- Erratic electrical behavior
Common Causes
- Short to ground on bus E
- Faulty control module
- Damaged wiring
- Poor connections
Diagnostic Steps
- Scan for communication codes
- Check bus E voltage levels
- Inspect wiring for shorts
- Test suspect modules
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