U0008high severityNetwork
High Speed CAN Communication Bus (-) High
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The CAN Low wire voltage is higher than expected, indicating a short to power.
Symptoms
- CAN bus failure
- Multiple communication errors
- Systems unresponsive
Common causes
- CAN L shorted to battery voltage
- Wiring harness damage
- Module fault driving CAN L high
Diagnostic steps
- Measure CAN L voltage
- Disconnect modules to isolate
- Inspect wiring for shorts to power circuits
- Check harness routing near power wires
Repair notes
Repair CAN L short to power. Ensure CAN wiring is properly separated from power wiring.
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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
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus
U0028
Vehicle Communication Bus A Performance