Engine Coolant Temperature (ECT) Switch
WARNING: This page is about a different car, the 2003 Lexus RX 300 and 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Engine Coolant Temperature (ECT) switch may also be called water temperature switch.
- Drain engine coolant. Remove No. 1 ECT switch. See COMPONENT LOCATIONS . Using ohmmeter, ensure there is continuity between terminals when coolant temperature is greater than 208°F (98°C). If there is no continuity, replace switch.
- Ensure there is no continuity between terminals when temperature is less than 190°F (88°C). If continuity exists, replace switch. Reinstall No. 1 ECT switch.
- Remove No. 2 ECT switch. Ensure there is continuity between terminals when coolant temperature is greater than 201°F (94°C). If there is no continuity, replace switch.
- Ensure there is no continuity between terminals when temperature is less than 181°F (83°C). If continuity exists, replace switch. Reinstall No. 2 ECT switch.