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Home >> Toyota >> 2008 >> Prius Base >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> SFI System >> DTC P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control >> Inspection Procedure
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Inspection Procedure

HINT:

  1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0125) 
    1. Connect Techstream to the DLC3.
    2. Turn the power switch ON (IG).
    3. Turn Techstream ON.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Code.
    5. Read the DTCs using Techstream.

      Result 

      RESULT CHART

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

      HINT:

      If any other codes besides P0125 are output, perform troubleshooting for those DTCs first.

    B:  GO TO DTC CHART 

    A: Go To Next Step 

  2. INSPECT THERMOSTAT 
    1. Check the valve opening temperature of the thermostat.

      OK: 

      Thermostat valve begins to open at temperature of 80 to 84°C (176 to 183°F) 

      HINT:

      Also check that the valve is completely closed at a temperature lower than specified above.

    NG: REPLACE THERMOSTAT 

    OK: REPLACE ENGINE COOLANT TEMPERATURE SENSOR