Inspection Procedure

DTC 22 Engine Coolant Temp. Sensor Circuit




1. CHECK VOLTAGE BETWEEN TERMINALS THW AND E2 OF ENGINE CONTROL MODULE CONNECTOR.



- Connect the Check Harness A.
- Turn ignition switch ON.
- Measure voltage between terminals THW and E2 of ECM connector.

OK if: Voltage...
@ 20°C (68°F): 0.5 - 3.4 volts
@ 80°C (176°F): 0.2 - 1.0 volts

- If OK check for momentary interruption.
- If not OK proceed to step 2.

2. CHECK ENGINE COOLANT TEMPERATURE SENSOR.
- Disconnect the engine coolant temperature sensor connector



- Measure resistance between terminals and check the readings against the chart in Fig. 11.

Fig. 11 - Table Of Values For Engine Coolant Temperature Sensor:

FIG.11
- If OK proceed to step 3.
- If not OK replace engine coolant temperature sensor.

3. CHECK FOR OPEN AND SHORT IN HARNESS AND CONNECTOR BETWEEN ENGINE CONTROL MODULE AND ENGINE COOLANT TEMPERATURE SENSOR.
- If OK check and replace ECM.
- If not OK repair or replace harness or connector.

NOTE: If diagnostic trouble codes DTC 22 (engine coolant temperature sensor circuit), DTC 24 (intake air temperature sensor circuit) and DTC 41 (throttle position sensor circuit) are output simultaneously, E2 (sensor ground) may be open.