Throttle Position Sensor: Description and Operation

THROTTLE POSITION POTENTIOMETER

The Throttle Position (TP) Potentiometer supplies the ECM with a signal describing the throttle opening. The ECM uses this information in its computations when the engine is loaded, for example during acceleration, and at idling.

The TP potentiometer consists of the following components:

^ Hub and wiper contacts (1)
^ Contact track (2)
^ Rheostat (3)

The hub and wiper contacts are rotated by the throttle spindle, varying the sensor output signal. The ECM delivers a 5 Volt supply to the contact track. The output signal varies between 0.5 Volts at the Closed-Throttle Position (CTP) and 4.2 Volts at Wide-Open Throttle (WOT).

The ECM adopts a substitute value if the signal from the TP potentiometer is lost or becomes faulty.

The potentiometer is mounted on the Throttle Body (TB).