Throttle Position Sensor: Description and Operation

Throttle Position Sensor Operation:

Closed Throttle Position Switch Operation:

PURPOSE
The throttle position sensor is a potentiometer type sensor that sends information on throttle blade position to the vehicle's ECM. The closed throttle position switch is a rotary contact type switch that sends confirmation of the throttle blade being closed to the ECM, for use in computing idle control strategy.

OPERATION
The throttle position sensor functions to convert the degree of opening of the throttle valve to voltage, and to input that voltage (as signals) to the engine control module. The engine control module, based upon those signals, then regulates the amount of fuel injection, etc.

The closed throttle position switch functions to convert (to HIGH/LOW-level voltage) data as to whether the accelerator is depressed or released, and to input that voltage (as signals) to the engine control module. The engine control module, based upon those signals, regulates the idle air control motor.

CONSTRUCTION
The throttle position sensor and the closed throttle position switch share a common housing and are replaced and adjusted at the same time.