1. Testing of Magnetic Pulse Type Crankshaft Position Sensor

① Testing the resistance of the crankshaft position sensor: Disconnect the connector and use a multimeter to measure the resistance between the terminals of the sensor. It should conform to the specifications in the attached table; otherwise, the sensor should be replaced.

② Testing the output signal of the crankshaft position sensor: Disconnect the connector of the crankshaft position sensor. When the engine is turned, there should be a pulse signal output between terminals G1-, G2-, and G-. If there is no pulse signal output, the sensor needs to be replaced.

③ Testing the gap between the sensor coil and the signal rotor: Use a feeler gauge to check the air gap between the signal rotor and the sensor coil protrusion. The gap should be 0.2~0.4mm. If the gap does not meet the requirements, it needs to be adjusted or replaced.

2. Testing of Photoelectric Crankshaft Position Sensor

The photoelectric crankshaft position sensor has two sets of photoelectric signal generators, which are centrally installed in the distributor.

During testing, disconnect the sensor connector, turn the ignition switch to "ON," and measure the power supply voltage. It should be 12V. Alternatively, connect a 12V battery between sensor terminals 2 and 1, and connect the ammeter between terminals 1 and 3, and 1 and 4. When the signal disc is rotated one revolution, the ammeter should swing once or four times, indicating 1mA each time. The voltage for different vehicle models should conform to the specifications in the attached table; otherwise, the photoelectric sensor should be replaced.

3. Testing of Hall Effect Crankshaft Position Sensors

① Inspection of Crankshaft Position and Angle Sensors: Use a multimeter in DC voltage mode to measure the power supply voltage of the crankshaft position and angle sensors. The normal value should be 12V. Use a multimeter in DC voltage mode to measure the output signal voltage of the sensor in the starting state. The crankshaft position signal voltage should be 0.8~0.9V, and the crankshaft angle signal voltage should be 2~3V.

② Measuring the Hall Sensor Output Voltage
Disconnect the ignition switch, open the distributor cap, disconnect the central high-voltage wire from the distributor cap and ground it. Disconnect the rubber sleeve from the ignition connector plug, but leave the plug plugged in. Connect the two probes of the voltmeter to terminals 3 and 6, as shown in Figure 5. Turn on the ignition switch and rotate the engine in the direction of engine rotation. Observe that the voltmeter reading should change between 0 and 7V, and the voltage should change 4 times after two crankshaft rotations. Otherwise, the Hall effect generator is faulty and should be replaced.

③ Simulating Hall Signal Generator Operation
Disconnect the ignition switch, open the distributor cap, and rotate the crankshaft so that the distributor trigger impeller is not in the air gap. Disconnect the central high-voltage wire from the distributor cap, leaving its end 5-7mm from the cylinder block. Turn on the ignition switch. Gently insert and remove a screwdriver into the air gap of the signal generator to simulate the movement of the trigger impeller in the air gap, as shown in Figure 5. If sparks appear at the end of the high-voltage line at this time, it indicates that the signal generator is working properly; if no sparks appear, it indicates that the signal generator is faulty and should be replaced.