Component Testing

Fig. 79 Engine Coolant Temperature Sensor Location-SOHC:

1. With the key off, disconnect wire harness connector from coolant temperature sensor (Fig. 79).

Fig. 27 Engine Coolant Temperature Sensor:

2. Connect a high input impedance (digital) volt-ohmmeter to terminals A and B (Fig. 27). The ohmmeter should read as follows:
- Engine/Sensor at normal operating temperature around 200°F should read approximately 700 to 1,000 ohms.
- Engine/Sensor at room temperature around 70°F ohmmeter should read approximately 7,000 to 13,000 ohms.

3. Test the resistance of the wire harness between the PCM 60-way connector terminal 28 and the sensor harness connector. Also check for continuity between PCM 60-way connector terminal 51 and the sensor harness connector. Refer to electrical diagrams for circuit information. If the resistance is greater than 1 ohm, repair the wire harness as necessary.