P1602high severityPowertrain
TCM Serial Communication Problem
on 2006 Kia Spectra 2.0L I4 · FWD
What this code means
The PCM has detected a serial communication problem with the Transmission Control Module. Data exchange between the PCM and TCM is interrupted or corrupted, preventing coordinated powertrain operation.
Symptoms
- Check Engine Light
- Transmission in limp mode
- Harsh shifting
- No upshifts or downshifts
- Cruise control inoperative
Common causes
- Faulty TCM
- CAN bus wiring damage
- Corroded CAN bus connector
- TCM power or ground issue
- PCM CAN bus driver failure
Diagnostic steps
- Check TCM power supply and ground connections
- Inspect CAN bus wiring between PCM and TCM
- Test CAN bus resistance (approximately 60 ohms between CAN-H and CAN-L)
- Attempt to communicate with TCM using scan tool
- Check for TCM-specific DTCs
Repair notes
Repair CAN bus wiring or connectors; replace the TCM if it has failed internally.
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P0002
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P0003
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P0004
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P0010
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P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
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