Throttle Position Sensor: Description and Operation

The throttle sensor responds to accelerator pedal movement. This sensor is a kind of potentiometer which transforms throttle valve position into output voltage, and emits the voltage signal to the ECU. The sensor detects the opening and closing speed of throttle valve and feeds the voltage signal to the ECU. Idle position of throttle valve is determined by the ECU receiving the signal from the throttle sensor. This system is called ``soft idle switch.'' It controls engine operation such as fuel cut. In addition the ``hard idle switch,'' which is built in the throttle sensor unit, is used for engine control when soft idle switch is malfunctioning.