Identification and Detection of Semiconductor Varistor-type Intake Air Pressure Sensor 6

② Check the output signal voltage of the manifold pressure sensor. Turn on the ignition switch, but do not start the engine. Remove the vacuum hose from the intake manifold and use a multimeter to measure the voltage between the PIM and Dang terminals of the ECU. During measurement, a vacuum should be applied to the sensor, with a vacuum degree between 13.3 and 66.77 kPa. Measure the voltage value between PIM and E2 with a multimeter, as shown in Table 2. The voltage inspection of the output signal of the manifold pressure sensor is shown in Figure 9.diode

Figure 8 Check the power supply voltage of the manifold pressure sensor Figure 9 Check the output signal voltage of the manifold pressure sensordiode

1V low voltage signal; When the throttle valve is fully opened, the manifold vacuum degree is low, the sensor resistance is small, and the sensor outputs a high voltage signal of 3.9-4.8V, as shown in Figure 11.

Figure 10 Connection circuit diagram between manifold pressure sensor and ECU Figure 11 Working principle diagram of manifold pressure sensor diode

Table 2 Voltage values between PIM-E2 at different vacuum degrees

① Check the voltage of the sensor power supply. Turn on the ignition switch and check that the voltage between terminal C and terminal A of the manifold pressure sensor is 4.5-5.5V. If the voltage is zero, then check the voltage between terminal 6 and terminal 4 of the ECU harness connector. If the voltage is 4.5-5.5V, it indicates that the sensor power wire is open or poorly connected. diode