Inspection Procedure

HINT:

• If DTCs P0115, P0116, P0117, P0118 and P0125 are output simultaneously, an ECT sensor circuit may be open or shorted. Perform the troubleshooting of DTC P0115, P0117 or P0118 first.
• Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0125) 
   1. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
   2. Turn the ignition switch ON and turn the intelligent tester ON.
   3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
   4. Read the DTCs.

      Result: 

      RESULT REFERENCE
      
      

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

      HINT:

      If any other codes besides P0125 is output, perform the troubleshooting for those codes first.

   B: GO TO RELEVANT 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.

      OK: 

      Valve opening temperature is 80 to 84°C (176 to 183°F) 

      HINT:

      Also check that the valve is completely closed below the opening temperature shown above.

   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 a modified cooling system.

   NG: REPAIR OR REPLACE COOLING SYSTEM 

   OK: REPLACE ENGINE COOLANT TEMPERATURE SENSOR