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DTC P0125: Insufficient Coolant Temperature For Closed Loop Fuel Control: Notes

  1. DTC detecting condition: 

    Detected when two consecutive driving cycles with fault occur.

    Trouble symptom: 

    Engine does not return to idle.

    NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Basic Diagnostic Procedure>PROCEDURE .
  1. CHECK DTC  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to OPERATION .

    Is DTC other than P0125 displayed? (Current code)

    Yes  : Check the appropriate DTC using the "Diagnostic Trouble Code (DTC)". Ref. to LIST .

    No  : Go to  2.

  2. CHECK ENGINE COOLANT  .

    Check the following items:

    • Amount of engine coolant
    • Engine coolant freeze
    • Contamination of engine coolant

    Is the check result OK?

    Yes  : Go to  3.

    No  : Fill or replace the engine coolant. Ref. to COOLING (H4DOTC)>Engine Coolant>REPLACEMENT .

  3. CHECK THERMOSTAT  .

    Check the thermostat. Ref. to COOLING (H4DOTC)>Thermostat>INSPECTION .

    Does the thermostat remain opened?

    Yes  : Replace the thermostat. Ref. to REMOVAL .

    No  : Go to  4.

  4. CHECK ENGINE COOLANT TEMPERATURE SENSOR  .

    Check the engine coolant temperature sensor. Ref. to INSPECTION .