Suitable for Volvo truck fuel pressure sensor 21634024

Detection of automobile throttle position sensor with switch output.

(1) Structure and circuit

Throttle position sensor with on-off output is also called throttle switch. It has two pairs of contacts, namely idle contact (IDL) and full load contact (PSW). A cam coaxial with the throttle valve controls the opening and closing of the two switch contacts. When the throttle valve is in the fully closed position, the idle contact IDL is closed, and the ECU judges that the engine is in idle working condition according to the closing signal of the idle switch, so as to control the fuel injection quantity according to the requirements of idle working condition; When the throttle valve is opened, the idle contact is opened, and the ECU controls the fuel injection under the transition condition from idle speed to light load according to this signal; The full-load contact is always open in the range from the fully closed position of the throttle to the middle and small opening. When the throttle is opened to a certain angle (55 for Toyota 1G-EU), the full-load contact begins to close, sending a signal that the engine is in full-load operation condition to ECU, and ECU performs full-load enrichment control according to this signal. Throttle position sensor with switch output for electronic control system of Toyota 1G-EU engine.

(2) Check and adjust the throttle position sensor with on-off output.

① Check the continuity between terminals on the bus.

Turn the ignition switch to the "OFF" position, unplug the throttle position sensor connector, and insert a thickness gauge with appropriate thickness between the throttle limit screw and the limit lever; Measure the continuity of idle contact and full load contact at the throttle position sensor connector with multimeter Ω.

When the throttle valve is fully closed, the idle contact IDL should be turned on; When the throttle valve is fully opened or nearly fully opened, the full load contact PSW should be turned on; At other openings, both contacts should be non-conductive. The details are shown in Table 1. Otherwise, adjust or replace the throttle position sensor.