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Home >> Toyota >> 2012 >> Matrix Base, Standard Trans >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 19 (Engine Control System (2AZ-FE) (Diagnostic Codes (P0010 - P0456)) >> SFI System >> DTC P0125: Insufficient Coolant Temperature for Closed Loop Fuel Control >> Procedure
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DTC P0125: Insufficient Coolant Temperature for Closed Loop Fuel Control: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0125) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
    5. Read DTCs.

      Result

      Result Proceed to
      P0125 A
      P0125 and other DTCs B

      HINT: 

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

    B → See step   4 

    A: Go to next step 

  2. INSPECT THERMOSTAT 
    1. Remove the thermostat. Refer to REMOVAL .
    2. Check the valve opening temperature of the thermostat.

      Standard Value

      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. Refer to INSTALLATION .

    NG → See step   5 

    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 → See step   6 

  4. GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART 
  5. REPLACE THERMOSTAT. Refer to  REMOVAL 
  6. REPLACE ENGINE COOLANT TEMPERATURE SENSOR. Refer to  REMOVAL