Throttle Position Sensor: Description and Operation

Fig. 26 Throttle Sensor-Soft/Hard Idle Switch:

The throttle sensor-soft/hard idle switch is mounted to the throttle shaft. It is a variable resistor (soft idle switch) and an open/close switch (hard idle switch). The variable resistor circuit (soft idle switch) in the sensor monitors the throttle angle and speed of throttle movement. It supplies a voltage signal to the ECU in response to throttle position. The open close switch (hard idle switch) circuit is used to signal the ECU when the throttle is in the idle position.