Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection

Engine Coolant Temperature Sensor:

TROUBLESHOOTING HINTS
Suspect the coolant temperature sensor or sensor circuit if fast idle speed is inadequate or the engine emits dark smoke during engine warm up.

SENSOR INSPECTION

CAUTION: Be careful not to touch the tool against the resin section of the connector when removing and installing.

1. Remove engine coolant temperature sensor from the intake manifold.
2. With temperature sensing portion of engine coolant temperature sensor immersed in hot water check resistance

Engine Coolant Temperature Sensor:

Temperature °C (°F) Resistance in k ohms

0 (32) 5.8

20 (68) 2.4

40 (104) 1.1

80 (176) 0.3

3. If the resistance deviates from the standard value greatly replace the sensor.

INSTALLATION
1. Apply sealant to threaded portion.
- Specified sealant: 3M NUT locking Part No. 4171 or equivalent
2. Install engine coolant temperature sensor and tighten it to specified torque.
- Sensor tightening torque: 30 Nm (22 ft lb)
3. Fasten harness connectors securely.

HARNESS INSPECTION

INSPECTION USING SCAN TOOL