Throttle Position Switch: Description and Operation

Throttle Position Switch:

PURPOSE
The throttle position switch supplies basic throttle position information to the ECU.

LOCATION
The throttle position switch is located on the throttle housing.

OPERATION
for Fuel Injection ECU:
The ECU supplies voltage (at two terminals) to the throttle switch. When the throttle valve is closed (idle position) or in the full load position, the switch grounds the ECU, allowing the current to flow from one of the two terminals. This indicates the throttle position to the ECU.

for Ignition ECU:
The fuel injection ECU supplies voltage via the ignition ECU to the throttle switch. When the throttle valve is closed (idle position) the switch grounds the ECU, allowing current to flow from the terminal. This indicates throttle position to the ignition ECU.