Troubleshooting
DTC P0115 Engine Coolant Temperature CircuitCIRCUIT DESCRIPTION
DTC Detection Condition:
A thermistor built into 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 in the intake air temp. circuit malfunction.
If the ECM detects the DTC P0115, it operates fail safe function in which the engine coolant temp. 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 the "CURRENT DATA".
Wiring Diagram:
Step 1:
Step 2:
Step 3 - 4:
Step 5:
INSPECTION PROCEDURE
HINT:
- If DTCs P0110, P0115 and P0120 are output simultaneously, E2 (sensor ground) 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 to determine 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 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.
2. Set the check mode.
3. Perform a simulation test.
4. Check the connector and terminal.
5. Handle the connector.