Throttle Position Sensor: Description and Operation

Throttle Position Sensor
The throttle position sensor is connected to the throttle valve shaft on the throttle body, and detects the throttle valve opening. The closed throttle position (idle position) is detected by means of the contact point which turns ON in that position. The throttle opening is detected by the potentiometer as follows. A 5-volt reference voltage is applied to the sensor from ECM and as its brush moves over the print resistance according to the throttle valve opening, the output voltage varies accordingly. By monitoring sensor output voltage, ECM detects the throttle valve opening. ECM uses the signal from TP sensor as one of the signals to control various devices. Also, ECM converts the voltage signal from TP sensor into ON/OFF signal and sends it to transmission control module, where it is used as one of the signals to control the automatic transmission.





Throttle Valve Opening Signal Output for A/T
Receiving the throttle valve opening signal from the throttle position sensor, ECM converts it into the duty signal (voltage signal) and sends it to transmission control module. Then transmission control module uses it as the signal to control the automatic transmission.