Troubleshooting
P0115 - Engine Coolant Temperature Circuit MalfunctionCIRCUIT DESCRIPTION
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.
DTC Detecting Condition:
If the ECM detects the DTC P0115, it operates the fail-safe function in which the engine coolant temperature is assumed to be 80°C (176°C).
HINT: After confirming DTC P0115, use the OBDII scan tool or hand-held tester to confirm the engine coolant temperature from the CURRENT DATA.
Wiring Diagram:
Step 1 - 2:
Step 3 - 4:
Step 5:
INSPECTION PROCEDURE
HINT:
- If DTCs P0110, P0115, P0120 and P1410 are output simultaneously, E2 (sensor ground) may be open.
- Read freeze frame data using hand-held tester or OBDII 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.
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 sensitivity to detect open circuits is increased. This makes it easier to detect intermittent problems.
1. Clear the DTC (See step 2).
2. Set the check mode (See step 3).
3. Perform a simulation test.
4. Check the connector and terminal.
5. Handle the connector.