Circuit Description

WARNING: This page is about a different car, the 2003 Lexus GS 430. However, it is still accessible from the selected car via links, so may be relevant.

The accelerator pedal position sensor is mounted on the accelerator pedal bracket and it has 2 sensors to detect the accelerator pedal position and a malfunction of the accelerator pedal position sensor. In the accelerator pedal position sensor, the voltage applied to pedal terminals VPA and VPA2 of the ECM changes between 0-5 volts, in proportion to the opening angle of the accelerator pedal. The VPA is a signal to indicate the actual accelerator pedal opening angle which is used for the engine control, and the VPA2 is a signal to indicate the information about the opening angle which is used for detecting a malfunction. The ECM judges the current opening angle of the accelerator pedal from these signals input from terminals VPA and VPA2, and the ECM controls the throttle motor based on these signals. If this DTC is stored, the throttle valve is locked at a certain opening angle. Electronically controlled throttle operation is cancelled until system returns to normal and the ignition switch is turned OFF. Possible cause is accelerator pedal position sensor.