Discover the Importance of ABS Speed Sensors
It's not until you need it in a close-call driving situation that you realize the importance of your anti-lock brake system. Wheel speed sensors, which can be found at eBay Motors, ensure your vehicle's ABS system functions during everyday commutes and in those crucial braking moments.
What is an ABS wheel speed sensor?An anti-lock braking system (ABS) wheel speed sensor measures a vehicle's wheel speed and transmits that data to the ABS control module. Most newer vehicles have four ABS wheel sensors, one for each wheel; however, some pickup trucks can have one or three sensors.
How an ABS speed sensor works?Most speed sensors are part of the vehicle's wheel hub. The sensor consists of a magnet and an electromagnetic coil. As the wheel rotates, it creates a magnetic field around the sensor. The coil registers the speed and transmits the data to the ABS control module.
Based on multiple data points, the ABS control module will determine if a wheel is nearing the point when it might lock up and start to skid. If so, the ABS will rapidly pulse the brake fluid pressure to slow down or stop the vehicle safely.
How do you know if your ABS speed sensor is bad?Wheel sensors are critical components in the ABS. If one fails, the ABS icon will light up. In addition, you can use an onboard diagnostics code reader to determine if the wheel sensor is at fault. You may also notice that it takes longer to stop when braking heavily or feel a loss of traction on a wet road.
You can also check the wheel speed sensor with a multimeter. Consult your vehicle's service manual to verify how to measure the sensor's resistance and compare it to the manual's specifications.
How do you replace a wheel ABS speed sensor?An ABS wheel speed sensor is a critical safety component. When it fails, it should be promptly replaced, and it is easy to replace with the proper tools. Each model may have a slightly different procedure, so refer to the manufacturer's instructions. Here are the basic steps:
- Make sure the engine is off and the vehicle is in park with the emergency brake on.
- Safely jack up the car, and remove the wheel with the defective sensor.
- Remove the sensor-retaining car bolt. It often is located at the bottom of the wheel assembly. You should spray the bolt with a penetrant to loosen it.
- Remove the sensor, and follow the sensor's wire harness to a connector. Disconnect the connector from the balance of the wiring harness.
- Clean the sensor-mounting area with brake cleaner, and use a clean rag to remove debris.
- Replace the wheel speed sensor, and reconnect the wire cable to the harness, using clips or brackets to keep the wiring snug.
- Replace the wheel, and lower the car to the ground.
- Test drive the car, and confirm that the ABS signal is no longer lit.