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Home >> Lexus >> 2008 >> GS 350 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC P0010 - P0159 >> DTC P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control >> Inspection Procedure
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Inspection Procedure

HINT:

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0125) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Select the following menu items: Powertrain/Engine and ECT/Trouble Codes.
    5. Read the DTCs.

      Result 

      DTC OUTPUT REFERENCE

      Display (DTC Output) Proceed to
      P0125 A
      P0125 and other DTCs B

      HINT:

      If any DTCs other than P0125 are output, troubleshoot those DTCs first.

    B :  GO TO DTC CHART

    A : Go to Next Step 

  2. INSPECT WATER INLET WITH THERMOSTAT (THERMOSTAT) 
    1. Remove the thermostat (See REMOVAL ).
    2. Check the valve opening temperature of the thermostat.

      Standard: 80 to 84°C (176 to 183°F) 

      HINT:

      In addition to the above check, confirm that the valve is completely closed when the temperature is below the standard.

    3. Reinstall the thermostat (See INSTALLATION ).

    NG : REPLACE WATER INLET WITH THERMOSTAT 

    OK : Go to Next Step 

  3. CHECK COOLING SYSTEM 
    1. Check for defects in the cooling system that might cause the system to be too cold, such as abnormal radiator fan operation or any modifications.

    NG : REPAIR OR REPLACE COOLING SYSTEM 

    OK : REPLACE ENGINE COOLANT TEMPERATURE SENSOR