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Troubleshooting

P0115 - Engine Coolant Temperature Circuit Malfunction

CIRCUIT DESCRIPTION

DTC Detection Condition:




A thermistor built in 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.






HINT: After confirming DTC P0115, use the hand-held tester or OBD II scan tool 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 and P0120 are output simultaneously, E2 (sensor ground) 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.

CHECK FOR INTERMITTENT PROBLEMS

HINT:
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.

a. Clear the DTCs.
b. Set the check mode.
c. Perform a simulation test.
d. Check the connector and terminal.
e. Handle the connector.