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DTC P0125: ECT Sensor Malfunction/Slow Response (2004-2005 models)

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  - Replace the ECT sensor.
    2. NO  - Intermittent failure, system is OK at this time. Check the thermostat and the cooling system.