How to Test the Crankshaft Position Sensor?
2 Answers
Methods for testing the crankshaft position sensor: 1. Disconnect its wiring connector and use a multimeter to measure the resistance between each terminal on the sensor. The readings should comply with the specifications in the attached table; otherwise, the sensor should be replaced. 2. Disconnect the wiring connector of the crankshaft position sensor. When turning the engine, there should be pulse signals output between the G1, G2, and G terminals. If no pulse signals are detected, the sensor needs to be replaced. Here are the relevant details: 1. Inspection of the crankshaft position and angle sensor. Use the DC voltage setting on a multimeter to measure the power supply voltage of the crankshaft position and angle sensor. The normal value should be 12V. Measure the output signal voltage of the sensor during startup using the DC voltage setting. The crankshaft position signal voltage should be 0.8–0.9V, and the crankshaft angle signal voltage should be 2–3V. 2. Measuring the output voltage of the Hall sensor. Turn off the ignition switch, open the distributor cap, remove the central high-voltage wire from the distributor cap and ground it. Remove the rubber sleeve from the ignition module connector, but keep the connector plugged in. Connect the voltmeter probes to terminals 3 and 6, turn on the ignition switch, and rotate the engine in the direction of engine rotation. Observe that the voltmeter reading should vary between 0–7V, and the voltage should change four times for every two crankshaft rotations. Otherwise, the Hall effect generator is faulty and should be replaced.
I often help people test crankshaft position sensors, and the method is actually quite simple. As a seasoned car enthusiast with years of experience, I believe visual inspection is the most basic first step: check for cracks or oil accumulation on the sensor housing to rule out physical damage. Then, use a multimeter to measure resistance—the normal range is typically between 200 and 1000 ohms. Significant deviation indicates internal issues. Don’t forget to inspect wiring connections; I’ve encountered cases where loose plugs caused signal interruptions. If you have diagnostic tools like an OBD-II scanner, plugging it in to read trouble codes is even more convenient—it directly tells you if the sensor is reporting errors. I also recommend testing while the engine is running to simulate real-world conditions. From a safety perspective, a faulty sensor can lead to misfires, engine stalling, or rough idling, so timely repairs can prevent breakdowns at high speeds. Based on my experience, regularly cleaning debris around the sensor is key to prevention, ensuring smoother vehicle performance.
