Throttle Full Close Switch: Description and Operation

Component Locations:

The throttle microswitch is mounted on the intake manifold. The microwitch is supplied by the ECU with a constant voltage signal (approx. 8 volts). Under deceleration, the circuit to the ECU is closed by the microswitch. When the ECU receives a closed circuit signal from the microswitch and the engine is above 900 RPM (normal operating temperature) fuel supply is cut-off by the action of the electro-hydraulic actuator, i.e. deceleration fuel cut-off. The result is less fuel consumption and lower over-all emissions. The speed at which deceleration cut-off occurs depends on coolant temperature; The lower the coolant temperature, the higher the speed at which restart of fuel injection begins.