U0115critical severityNetwork
Lost Communication with ECM/PCM B
on 2015 Kia Forte 1.8L I4 · FWD
What this code means
Cannot communicate with the secondary Engine Control Module on vehicles with dual ECMs.
Symptoms
- Partial engine management failure
- Some cylinders not controlled
- Reduced power
- Check Engine Light
Common causes
- ECM B power failure
- CAN bus wiring
- ECM B failure
- Fuse blown
- Connector issue
Diagnostic steps
- Check ECM B fuse
- Test power and ground
- Check CAN wiring
- Try direct communication with ECM B
- Compare ECM A and B communication status
Repair notes
Dual ECM vehicles are less common. Check power supply to secondary ECM.
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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