Close

OBD II Fault Code

  • OBD II P0666

    OBD-II Code Transmission may not shift properly is defined as a PCM/ECM/TCM Internal Temperature Sensor "A" Circuit

    The engine control module (PCM) and/or Transmission Control Module has a temperature sensor built in to prevent the module from overheating. If the control module cannot accurately determine its own temperature, it will set code P0666.

    Transmission may not shift properly Symptoms

    • Decreased engine performance
    • Transmission may not shift properly

    Common Problems That Trigger the P0666 Code

    • Powertrain Control Module (PCM) failure
    • Transmission Control Module (TCM) failure
    • Wiring issue
    Not the OBD-II Code You're Looking For?

    No comments yet...

    Sign in to comment