DTC P2122 Throttle/Pedal Position Sensor/Switch "D" Circuit Low Input: General Description

APS (Acceleration Position Sensor) measures driver's accelerating intension using a potentiometer and APS signal is transmitted to the PCM. The pedal's position is converted as voltages of potentiometer in the APS. The absence of a mechanical link between the accelerator pedal and throttle valve presents a risk of loss of control of the engine in the event of a failure of the component. Therefore, APS has the two potentiometers whose slides are mechanically solid. APS 2 decides whether or not APS 1 & 2 is faulty.