Identification and Detection of Semiconductor Varistor-type Intake Air Pressure Sensor 7

② Inspection of sensor signal voltage. When the ignition switch is turned on and the engine is not started, check the voltage between output terminal B and terminal A, which should be 4-5V; when the engine is idling, the voltage at terminal B should drop to 1.5-2.1V; when the throttle is wide open, the voltage at terminal B should increase. If the voltage on terminal 1 of the ECU harness connector plug is checked, it should be the same as the voltage on terminal B. If the inspection results do not comply with the above regulations. Indicating that the sensor signal line is open, the connector plug is loose, or there is a fault with the sensor.diode

③ Check the connection of the negative wire of the sensor. Use the resistance range of a multimeter to check the resistance between sensor A terminal and the engine cylinder block. The value should be less than 0.5 Ω. If the resistance is too high, it indicates a broken negative wire or poor contact of the ECU connector plug.diode

④ Check the connection of the vacuum hose. The vacuum hose between the manifold pressure sensor and the engine throttle body should not leak air. Otherwise, it will affect the performance of the sensor and cause unstable engine operation. If the pipe connection is poor, it should be firmly connected to prevent air leakage; If the tube is aging and has cracks, it should be replaced.diode