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Home >> Lexus >> 2008 >> RX 400h AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> SFI System >> DTC P0116 Engine Coolant Temperature Circuit Range / Performance Problem >> Inspection Procedure
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Inspection Procedure

HINT:

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0116) 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch to the ON position.
    3. Turn the tester ON.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Code.
    5. Read the DTCs.

      Result 

      RESULT CHART

      Display (DTC output) Proceed to
      P0116 A
      P0116 and other DTCs B

    B: GO TO DTC CHART 

    A: Go to next step 

  2. INSPECT 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 THERMOSTAT 

    OK: REPLACE ENGINE COOLANT TEMPERATURE SENSOR