Throttle Position Sensor: Description and Operation

THROTTLE POSITION (TP) SENSOR




The Throttle Position (TP) sensor (3) is located on the side of the throttle body. The TP sensor detects the throttle valve opening. The TP sensor is a potentiometer. The potentiometer is connected to the throttle valve shaft on the throttle body and is responsible for sending the throttle position signal to the Powertrain Control Module (PCM).

A 5-volt reference voltage is applied to the TP sensor from the PCM. The voltage reading at the PCM changes as the throttle plate opening increases. The PCM can calculate the throttle valve opening by monitoring the TP sensor output voltage. The TP sensor signal is one of the significant inputs used by the PCM to control the following:
^ Idle Air Control (IAC) valve operation
^ Exhaust Gas Recirculation (EGR) valve operation
^ Ignition timing
^ Fuel delivery
^ OBD 2 system diagnostics