Throttle Position Sensor: Description and Operation

The Throttle Position (TP) Sensor is a variable resistor that provides the ECM with an input signal (voltage) that represents throttle blade position. The sensor is connected to the throttle blade shaft. As the position of the throttle blade changes, the resistance of the TP Sensor changes. The ECM supplies a 5 V reference voltage to the TP Sensor. The TP Sensor output voltage (input signal to the ECM) represents the throttle blade position. This will usually vary from around 0.25 V at minimum throttle opening, to around 4.7 V at wide open throttle.