Detailed explanation of automobile engine technology throttle position sensor

4. Switch electric shock throttle position sensor

(1) Structural principle

The switch contact type throttle position sensor is also called the throttle switch. It has two pairs of contacts, namely the idle contact (IDL) and the high load contact (PSW). In the figure below, there is a cam-controlled active contact (TL or E) coaxial with the throttle, which opens and closes the two switch contacts respectively according to the state of the throttle. When the throttle is in the fully closed position, the idle contact IDL is connected to the active contact TL or E. The ECU determines that the engine is in the idle condition based on the idle signal, and thus controls the engine operation according to the requirements of the idle condition. When the throttle is opened, the idle contact is opened, and the ECU controls the engine operation from the idle to the low load transition condition based on this signal; the high load contact is always in the disconnected state within the range of the throttle from the fully closed position to the small and medium opening. When the throttle is opened to a certain angle, the high load contact is connected to the active contact TL or E, sending a signal to the ECU that the engine is in the full load operation condition, and the ECU performs full load enrichment control based on this signal.