Throttle Position Sensor: Description and Operation

Throttle Position Sensor (TPS):

PURPOSE
The Throttle Position Sensor (TPS) is a non-adjustable potentiometer that senses throttle angle and relays the information to the ECM. This input to the ECM is used to control the fuel system and most of the ECM outputs.

OPERATION
The TPS has internally three circuits. One to ground, the other from the ECM as a 5.0 volt reference source and a third circuit is used by the ECM to measure the output voltage. As the throttle angle changes (pressing down on accelerator pedal) the TPS voltage output varies from about .5 volt at idle to about 4.9 volts at wide open throttle (WOT).

LOCATION
Side of throttle body opposite of throttle lever.