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DTC P0125: ECT Sensor Malfunction/Slow Response (2006 model)

NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Start the engine, and let it idle.
  2. Check the ECT SENSOR in the DATA LIST with the HDS.

    Is about 86°F (30°C) or less, or 2.61 V or more indicated? 

    1. YES  - Go to step 3.
    2. NO  - Intermittent failure, system is OK at this time. Check the thermostat and the cooling system.
  3. Let the engine idle 6 minutes.
  4. Check the ECT SENSOR in the DATA LIST with the HDS.

    Is about 86°F (30°C) or less, or 2.61 V or more indicated? 

    1. YES  - Go to step 5.
    2. NO  - Intermittent failure, system is OK at this time. Check the thermostat and the cooling system.
  5. Turn the ignition switch OFF.
  6. Replace the ECT sensor.
  7. Turn the ignition switch ON (II).
  8. Reset the ECM with the HDS.
  9. Do the ECM idle learn procedure (see ECM IDLE LEARN PROCEDURE ).
  10. Allow the engine to cool to between 23°F (-5°C) and 77°F (25°C).
  11. Start the engine, and let it idle 20 minutes.
  12. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    1. YES  - If DTC P0125 is indicated, check for poor connections or loose terminals at the ECT sensor and the ECM, then go to step  1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC TROUBLESHOOTING 
    2. NO  - Troubleshooting is complete.