P0668
PCM/ECM (Engine Control Module) /TCM Internal Temperature Sensor Circuit Low
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0668 means
- The fault code P0668 indicates that there is an issue with the internal temperature sensor circuit in the Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM). This may cause the vehicle to exhibit poor performance or not start at all.
Possible symptoms
- Poor vehicle performance
- Difficulty starting the vehicle
- Illuminated check engine light
- Reduced engine power or acceleration
Possible causes
- Faulty internal temperature sensor within ECM/TCM
- Wiring or connector issues in the internal temperature sensor circuit
- PCM/ECM/TCM failure
Related parts
- Engine Control Module (ECM) Temperature Sensor: ECM is the part of the car computer that controls the engine system and performance. Engine Control Module (ECM) Temperature Sensor monitors the temperature of the ECM. Problems lead to poor fuel economy, engine stalling & unwanted engine vibrations
Possible solutions
- Replace the faulty internal temperature sensor
- Check and repair any damaged wiring or connections in the circuit
- Replace the PCM/ECM/TCM if necessary
Free on OBD DashX
P0668 on OBD DashX
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