Circuit Description
WARNING: This page is about a different car, the 2003 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
Throttle motor is operated by ECM and opens and closes throttle valve. Opening angle of throttle valve is detected by throttle position sensor which is mounted on throttle body. It provides feedback to ECM to control throttle motor to make throttle valve opening angle correct in response to driving condition. If malfunction is detected, ECM shuts down power for throttle motor, and throttle valve is fully closed by return spring. Throttle valve is locked at a certain opening angle. Also, entire electronically controlled throttle operation is cancelled until system returns to normal and ignition switch is turned off.
Possible causes are:
- Faulty throttle control motor circuit.
- Faulty throttle control motor.
- Faulty throttle body.
- Faulty throttle valve.