Engine Coolant Temperature Sensor
WARNING: This page is about a different car, the 2003 Toyota RAV4, 2002 Toyota RAV4, 2002 Toyota Highlander, 2001 Toyota RAV4, and 2001 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.
Engine Coolant Temperature (ECT) sensor delivers input signal to ECM, indicating engine coolant temperature. ECT sensor is located at left side of engine, near upper radiator hose.