P0666
PCM/ECM (Engine Control Module) /TCM Internal Temperature Sensor A Circuit
Generic code
Computer Output Circuit
High severity
Hard repair
Free on OBD DashX
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What P0666 means
- The fault code P0666 indicates that there is an issue with the internal temperature sensor of the Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM). This may result in poor performance and increased emissions.
Possible symptoms
- Illuminated check engine light
- Poor performance
- Increased emissions
Possible causes
- Failed internal temperature sensor
- Faulty wiring or connections in the circuit
- Corroded electrical connections
- Failed PCM, ECM, or TCM
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 internal temperature sensor
- Check and repair any damaged wiring or connections
- Clean any corroded electrical connections
- Replace the PCM, ECM, or TCM if necessary
Free on OBD DashX
P0666 on OBD DashX
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