How to Test the Condition of a Wheel Speed Sensor?
2 Answers
Methods to test the condition of a wheel speed sensor: 1. Check the gap between the wheel speed sensor and the gear ring. The normal standard value for the front wheel is 1.10 to 1.97mm, and for the rear wheel, it is 0.42 to 0.80mm. If the gap is too large, it will directly affect the sensor's data collection and accuracy. 2. Inspect the output voltage section. First, lift the vehicle to raise the tires off the ground and release the parking brake. 3. Remove the ABS wheel speed sensor wiring harness connector and proceed with direct measurement. 4. Rotate the wheel at a speed of 1 revolution per second and measure the output voltage with a multimeter. The normal range for the front wheel is 190 to 1140mV, and the rear wheel should exceed 650mV. If these standards are met, it indicates that the wheel speed sensor is functioning properly at this time.
As a seasoned driver with nearly 20 years of experience, I primarily check the ABS warning light to determine if a wheel speed sensor is faulty. The most common signs of a sensor issue are when the ABS light stays on constantly or flickers during turns, which may cause unstable braking. When I troubleshoot, I first inspect around the tires: crouching down to see if the sensor wiring is corroded by mud or water, checking for loose connectors, and sometimes dust buildup can also trigger false alarms. If the light remains on, I take it to a professional repair shop to use their diagnostic tools to confirm which specific wheel's sensor has failed. Wheel speed sensors are crucial for the anti-lock braking system, especially in rainy or snowy conditions—ABS failure can lead to skidding during braking and increase accident risks. So don't delay; early detection and repair prioritize safety.
