U0005high severityNetwork
High Speed CAN Communication Bus (+) High
on 1996 Cadillac Eldorado ETC 4.6L V8 Northstar · FWD
What this code means
The CAN High wire voltage is higher than expected, indicating a short to battery voltage.
Symptoms
- CAN bus communication failure
- Multiple module faults
- Warning lights on
Common causes
- CAN H wire shorted to battery power
- Wiring harness damage
- Module internal fault driving CAN H high
Diagnostic steps
- Measure CAN H voltage (should not exceed 4V)
- Inspect wiring for shorts to power wires
- Disconnect modules to isolate fault
- Check for wiring harness rub-through
Repair notes
Repair the short to power on CAN H. Often caused by wiring harness rubbing against sharp edge.
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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
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
U0011
Control Module Communication Bus A Low