Error code
OBD2 P0668
OBD2P0668
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
PCM/ECM/TCM Internal Temperature Sensor Circuit Low.
Severity
moderateCan drive but may experience performance issues or increased emissions.
Summary
P0668 indicates that the internal temperature sensor in the Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM) is reporting a lower than expected voltage, suggesting an issue with the circuit.
Common Causes
- Wiring short to earth
- Faulty internal temperature sensor
Fixes
- Replace the faulty internal temperature sensor in the PCM/ECM/TCM.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More OBD2 codes
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- P0605Internal Control Module Read Only Memory (ROM) Error
- P0606ECM/PCM Processor
- P0607Control Module Performance
- P0608Control Module VSS Output 'A'
- P0609Control Module VSS Output 'B'
- P0610Control Module Vehicle Options Error
- P0611Fuel Injector Control Module Performance