Troubleshooting

DTC P0115 Engine Coolant Temperature Circuit

CIRCUIT DESCRIPTION

Detection Item:

A thermistor built in the engine coolant temp. sensor changes the resistance value according to the engine coolant temp.

The structure of the sensor and connection to the ECM is the same as those of the intake air temperature circuit malfunction.

If the ECM detects the DTC P0115, it operates fail-safe function in which the engine coolant temperature is assumed to be 80 °C (176 °F).






HINT: After confirming DTC P0115, use the OBD II scan tool or hand-held tester to confirm the engine coolant temperature from CURRENT DATA.

Wiring Diagram:

Step 1 - 2:

Step 3 - 4:

Step 5:

INSPECTION PROCEDURE

HINT:
- If different DTCs that are related to different systems are output simultaneously while terminal E2 is used as a ground terminal, terminal E2 may be open.
- Read freeze frame data using hand-held tester or OBD II scan tool, as freeze frame data records the engine conditions when a 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.