U0066
NetworkModule Communicationhigh severityControl Module Communication Bus F Shorted To Bus F High
What U0066 Means
The low side of bus F is shorted to the high side, corrupting the data signal. This typically stops communication across the affected network.
Symptoms
- Multiple modules offline
- Warning lights active
- Erratic vehicle behavior
Common Causes
- Bus F wires shorted together
- Pinched or damaged harness
- Faulty connector
- Failed control module
Diagnostic Steps
- Scan all modules
- Check for short between bus F high and low
- Inspect harness for damage
- Repair wiring or replace module
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