Accelerator Pedal Position Sensor (APS)

The Accelerator Pedal Position Sensor (APS) is installed on the accelerator pedal module and detects the angle of the accelerator pedal. The APS is one of the most important sensors in the engine control system, so it consists of two sensors that have individual power and ground lines. The second sensor monitors the first sensor, and its output voltage is half that of the first one. If the ratio of sensors 1 and 2 is outside the allowable range (approximately 1/2), the diagnostic system determines that it is abnormal.