Monitor Description

The accelerator pedal position sensor is equipped with 2 signal outputs (elements), VPA and VPA2. VPA signals are used to detect actual accelerator pedal angles, which is useful for engine control. VPA2 signals are used for detecting malfunctions in VPA. These elements vary their resistance according to how much the accelerator pedal is depressed. The ECM applies a regulated reference voltage to the throttle position sensor "+" terminal and calculates the amount of the accelerator pedal depression based on the voltages present at the throttle position sensor "signal" terminals. When the amount of the accelerator pedal depression is small, the output voltages of these elements are low. When it is large, the output voltages are high. If the ECM detects that the output voltage of the element(s) is out of the normal range, the ECM will conclude that the accelerator pedal position sensor is malfunctioning and set a DTC.