Accelerator Pedal Position Sensor

WARNING: This page is about a different car, the 2011 Jaguar XK and 2010 Jaguar XK. However, it is still accessible from the selected car via links, so may be relevant.

Courtesy of JAGUAR CARS, INC.

The accelerator pedal position (APP) sensor allows the engine control module (ECM) to determine the driver requests for vehicle speed, acceleration and deceleration. The engine control module (ECM) uses this information to determine the setting of the electronic throttle.

The accelerator pedal position (APP) sensor is installed on the pedal box and secured with three screws. A six pin electrical connector provides the interface with the vehicle harness. The accelerator pedal is connected to a spindle on the right-hand (RH) side of the accelerator pedal position (APP) sensor.

The accelerator pedal position (APP) sensor is a twin track potentiometer. Each track receives an independent power supply from the engine control module (ECM) and returns an independent analog signal to the engine control module (ECM). Both signals contain the same positional information, but the signal from track 2 is half the voltage of the signal from track 1 at all positions.

If both signals have a fault, the engine control module (ECM) adopts a limp home mode, which limits the engine speed to 2000 rev/min maximum.

The engine control module (ECM) constantly checks the range and plausibility of the two signals and stores a fault code if it detects a fault.