Engine Coolant Temperature (ECT) Sensor
WARNING: This page is about a different car, the 2003 Lexus SC 430, 2003 Lexus LS 430, 2003 Lexus IS 300, 2003 Lexus GS 430, and 2003 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
- Ensure ignition is off. Locate ECT sensor. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION table. Remove ECT sensor.
- Place probe end of ECT sensor and thermometer in container of water. Attach ohmmeter between ECT sensor terminals. Heat water and note that resistance is within specification in relation to temperature. See Fig 1. Replace ECT sensor if resistance is not within specification.
- Using NEW gasket, install ECT sensor. Tighten ECT sensor to 14 ft. lbs. (19 N.m). Fill cooling system.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR LOCATION
| Model | Location |
|---|---|
| GS300 | Left Front Of Cylinder Head; Black 2-Pin Connector With Black/Red & Brown Wires |
| GS430 | Near Throttle Body; Black 2-Pin Connector With White/Green & White/Black Wires |
| IS300 | Left Front Of Cylinder Head; Green 2-Pin Connector With Red & Brown Wires |
| LS430 | Near Throttle Body; Black 2-Pin Connector With Red/Blue & Brown Wires |
| SC430 | Near Throttle Body; Black 2-Pin Connector With White/Green & White/Black Wires |