DTC P0116 Engine Coolant Temperature Circuit Range / Performance Problem: Wiring Diagram

Fig 1: Engine Coolant Temperature Circuit Wiring Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

• If DTC P0115, P0116, P0117, P0118 and P0125 are output simultaneously, 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 a malfunction is 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 P0116) 

   Result 

   RESULT PROCEDURE CHART
   
   

   Display (DTC output)	Proceed to
   P0116	A
   P0116 and other DTCs	B

   B : GO TO  RELEVANT DTC CHART  

   A : GO TO NEXT STEP. 

2. INSPECT THERMOSTAT 
   1. Remove the thermostat (REMOVAL ).
   2. Check the valve opening temperature of the thermostat.

      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.

   NG : REPLACE THERMOSTAT 

   OK : REPLACE ENGINE COOLANT TEMPERATURE SENSOR