The engine coolant temperature sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the ECM. The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P0125 is displayed with P0116, first perform the trouble diagnosis for DTC P0116. Refer to See: P0116.
If DTC P0125 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117, P0118. Refer to See: P0117.
DTC CONFIRMATION PROCEDURE 1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
Turn ignition switch OFF and wait at least 10 seconds.
Turn ignition switch ON.
Turn ignition switch OFF and wait at least 10 seconds. >> GO TO 2.
2.CHECK ENGINE COOLANT TEMPERATURE SENSOR FUNCTION With CONSULT-III
Turn ignition switch ON.
Select "DATA MONITOR" mode with CONSULT-III.
Check that "COOLAN TEMP/S" is above 10°C (50°F) . With GST
Follow the procedure "With CONSULT-III" above.
Is the temperature above 10°C (50°F) ?
YES >> Inspection END
NO >> GO TO 3. 3.PERFORM DTC CONFIRMATION PROCEDURE With CONSULT-III
Start engine and run it for 65 minutes at idle speed. If "COOLAN TEMP/S" increases to more than 10°C (50°F) within 65 minutes, stop engine because the test result will be OK.
CAUTION: Never overheat engine.
Check 1st trip DTC. With GST
Follow the procedure "With CONSULT-III" above.
Is 1st trip DTC detected?
YES >> Diagnosis Procedure
NO >> Inspection END