Circuit Description

A thermistor built into engine coolant temperature sensor changes resistance value according to engine coolant temperature. Structure of sensor and connection to ECM is same as in intake air temperature circuit malfunction. See DTC P0110: INTAKE AIR TEMPERATURE CIRCUIT MALFUNCTION . If ECM detects DTC P0115, it operates fail safe function in which engine coolant temperature is assumed to be 176°F (80°C).

Detecting condition of DTC is when there is an open or short in engine coolant temperature sensor circuit. After confirming DTC P0115, use hand-held tester or OBD II scan tool to confirm engine coolant temperature from CURRENT DATA. See IDENTIFYING ENGINE COOLANT TEMPERATURE  table.