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

Fig. 26 Air temperature (TA) & coolant temperature (TW) sensor test connections:

Fig. 27 Air temperature (TA) & coolant temperature (TW) sensor specifications:

1. Disconnect sensor electrical connectors, then remove sensor from inlet of manifold/thermostat housing on Accord and Prelude models or from inlet of manifold/cylinder head on CRX Si and Civic models.
2. Place sensor in cold water, Fig. 26, and slowly heat sensor while measuring resistance between sensor terminals.
3. On Accord and Prelude resistance should be 980-1340 ohms at 26°C (104°F) and 220-350 ohms at 80°C (176°F), and resistance drop should follow curve shown in Fig. 27 as sensor is heated. On Civic and CRX resistance should be 980-1340 ohms at 23°C (95°F) and 220-350 ohms at 80°C (176°F), and resistance drop should follow curve shown in Fig. 28 as sensor is heated.
4. If resistance is not as specified, replace sensor.