U0065
NetworkModule Communicationhigh severityControl Module Communication Bus F Low
What U0065 Means
The voltage on the F communication bus is lower than expected, disrupting module data transfer. Modules may drop offline intermittently or fully.
Symptoms
- Communication faults stored
- Intermittent module dropout
- Dash warning lights
Common Causes
- Bus F wiring shorted low
- High resistance in bus wiring
- Poor ground connection
- Faulty control module
Diagnostic Steps
- Scan network for U-codes
- Check bus F signal voltage
- Inspect wiring and connectors
- Repair circuit or replace module
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