Inspection Procedure

HINT:

• If any of DTCs P0115, P0116, P0117 or P0118 are set simultaneously with DTC P0125, the Engine Coolant Temperature (ECT) sensor may have an open or a short circuit. Troubleshoot those DTCs first.
• Read freeze frame data using an intelligent tester or OBD II scan tool. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0125) 
   1. Connect an intelligent tester or OBD II scan tool to the DLC3.
   2. Turn the ignition switch to ON.
   3. Turn the tester or scan tool ON.
   4. On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
   5. Read DTCs.
   6. If using an OBD II scan tool, refer to the instruction manual.

      Result 

      DTC RESULT DESCRIPTION
      
      

      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 THERMOSTAT 
   1. Remove the thermostat (See INSPECTION ).
   2. Check the valve opening temperature of the thermostat (See INSPECTION ).

      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 INSPECTION ).

   NG: REPLACE 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.

      Result: 

      Cooling system is normal. 

   NG: REPAIR OR REPLACE COOLING SYSTEM 

   OK : REPLACE ENGINE COOLANT TEMPERATURE SENSOR