Throttle Position Sensor: Description and Operation

Throttle Position Sensor Circuit:

Purpose:
The TPS provides the PCM/TCM with information regarding throttle position.

Operation:
The TPS is a potentiometer with one end connected to 5 volts from the PCM/TCM and the other to ground. A third wire is connected to the PCM/TCM to measure the voltage from the TPS.

As the throttle valve angle is changed, accelerator pedal moved, the output of the TPS also changes. At a closed throttle position, the output of the TPS is low, approximately .5 volts. As the throttle valve opens, the output increases so that at wide open throttle, the output voltage should be approximately 5 volts.

Location:
The TPS is mounted on the injection pump.