Throttle Position Sensor: Description and Operation

TP Sensor:

PURPOSE:
The Throttle Position (TP) sensor is connected to the throttle shaft on the throttle body unit. It is a potentiometer with one end connected to 5 volts from the control module and the other to ground. A third wire is connected to the control module to measure the voltage from the TP sensor. As the throttle valve angle is changed (accelerator pedal moved), the output of the TP sensor also changes. At a closed throttle position, the output of the TP signal is low (approximately 0.5 volt). As the throttle valve opens, the output increases so that, at Wide Open Throttle (WOT), the output voltage should be approximately 4.5 volts.

By monitoring the output voltage from the TP sensor, the control module can determine fuel delivery based on throttle valve angle (driver demand).