Acceleration Control - Description & Operation

Fig 1: Accelerator pedal, right-hand drive vehicles

Courtesy of JAGUAR CARS, INC.

Fig 2: Accelerator pedal, left-hand drive vehicles

Courtesy of JAGUAR CARS, INC.

When the accelerator pedal is pressed, the engine control module (ECM) monitors the angle of the accelerator pedal through the accelerator pedal position (APP) sensor. Refer to Electronic Engine Controls article. The APP sensor is connected to the accelerator pedal through an accelerator cable.

The ECM then provides an output, based on the accelerator pedal position, which drives a DC motor to position the throttle to the required angle. The throttle position is monitored by two sensors for rational value.

The ECM has the necessary safety features to monitor the correct operation of all the components. Depending on the failure state, the ECM can put acceleration control system into an appropriate safe state, from restricting the RPM to limphome mode.