Troubleshooting
DTC P0115 ENGINE COOLANT TEMPERATURE CIRCUIT MALFUNCTIONCIRCUIT 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 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 hand-held tester or OBD II scan tool to confirm the engine coolant temperature from "CURRENT DATA".
Wiring Diagram:
Step 1 - 3:
Step 4 - 5:
INSPECTION PROCEDURE
HINT:
- If DTC P0100 (Mass Air Flow Meter Circuit Malfunction), P0101 (Mass Air Flow Meter Circuit Range/Performance Problem), P0110 (Intake Air Temperature Circuit Malfunction), P0115 (Engine Coolant Temperature Circuit Malfunction), P0120 (Throttle/Pedal Position Sensor/Switch "A" Malfunction) are output simultaneously, E1, E2 etc. (Sensor Ground system) may be open.
- Read freeze frame data using 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 warmed up or not, the air-fuel ratio lean or rich, etc. at the time of the malfunction.
CHECK FOR INTERMITTENT PROBLEMS
Hand-held tester only:
By putting the vehicle's ECM in the check mode, 1 trip detection logic is possible instead of 2 trip detection logic and the sensitivity to detect open circuits is increased. This makes it easier to detect intermittent problems.
1. Clear the DTC.
2. Set the check mode.
3. Perform a simulation test.
4. Check the connector and terminal.
5. Handle the connector.