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Home >> Toyota >> 2008 >> Prius Base >> 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

  1. READ OUTPUT DTC 
    1. Connect Techstream to the DLC3.
    2. Turn the power switch ON (IG) and turn the tester on.
    3. Select the following menu items: Powertrain / Engine and ECT / Trouble Code.
    4. 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. Measure the valve opening temperature of the thermostat.

      Standard temperature: 

      80°C to 84°C (176°F 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