Throttle Position Sensor: Description and Operation

Throttle Position Sensor:

PURPOSE
The sensor is a variable resistor (potentiometer) that is used by the Engine Control Module (ECM) to detect throttle movement and position.

OPERATION
A 5 volt reference signal is applied from the ECM and a ground signal. When the throttle is opened the sensor resistance changes which is read as a varying voltage signal. At idle position the sensor voltage is approx. 0.5 Volts and approx. 4.5 Volts at full throttle.