Heated Oxygen Sensor (All Models)
WARNING: This page does not describe the selected car, but rather 17 other vehicles, including the 2003 Toyota Tundra, 2003 Toyota Tacoma, 2003 Toyota Sienna, 2003 Toyota Sequoia, and 2003 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.
Heated oxygen sensor monitors exhaust gas oxygen content and delivers an input signal to Engine Control Module (ECM). ECM may use input signal for determining ignition timing (spark advance) and for controlling fuel injection system. Some models may be equipped with more than one heated oxygen sensor. A heater is used to warm oxygen sensor to improve heated oxygen sensor detection operation. Heater is controlled by ECM.