Accelerator Pedal Position Sensor

It has two independent signals that are compared for safety. It replaced the throttle cable in drive-by-wire systems. It is often built into the pedal unit. Floor mats that press the pedal or block its travel can cause unexpected behaviour; keep them secured. Some cars use the pedal sensor for kick-down detection.

The engine control unit reads both signals and sets throttle opening accordingly.

Signal mismatch triggers limp mode with reduced power. Faults are often fixed by replacing the pedal unit.