U0012moderate severityNetwork
Control Module Communication Bus A Shorted To Bus A High
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The low side of communication bus A is shorted to the high side, corrupting data traffic. This causes loss of communication between modules.
Symptoms
- Communication error codes
- Warning lights illuminated
- Loss of module function
Common causes
- Wiring short between bus A high and low
- Chafed harness insulation
- Faulty control module
- Damaged connector
Diagnostic steps
- Scan for stored U-codes
- Check resistance between bus A wires
- Inspect harness for pinched wires
- Test individual modules
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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
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus