Troubleshooting

P0116 - Engine Coolant Temperature Circuit Range/Performance Problem

CIRCUIT DESCRIPTION

DTC Detecting Condition:

A thermistor built into the engine coolant temperature sensor changes the resistance value according to the engine coolant temperature.

The structure of the sensor and connection to the ECM is the same as in "Intake Air Temperature Circuit Malfunction".

Steps 1 - 2:

INSPECTION PROCEDURE

HINT:
- If DTCs P0115 and P0116 are output simultaneously, engine coolant temperature sensor circuit may be open. Perform troubleshooting of DTC P0115 first.
- Read freeze frame data using LEXUS hand-held tester or OBD II scan tool. Because freeze frame records the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.