A car wouldn’t be complete without a wheel speed sensor. They are vitally important because they relay data regarding each wheel’s speed to the car’s anti-lock brake system (ABS) and engine control module (ECM). This data is utilized to keep the wheels from seizing up during heavy braking, which might result in the car rolling out of control. Learn more about wheel speed sensors and their symptoms, replacement, kinds, and more in this in-depth article.

What Is A Wheel Speed Sensor? 

Vehicles have small electrical devices called wheel speed sensors installed close to the hub assembly of each wheel. A magnet and a wire coil make up its components. Such as the wheel rotates, the sensor’s magnet creates an alternating current in the wire coil. This current’s frequency increases as the wheel’s rotational velocity increases.  

The ABS wheel speed sensor is an essential part of the system. The ABS control module receives information about each wheel’s rotational speed and responds by adjusting the braking force in emergency stops or when the road is wet. 

Bad Wheel Speed Sensor Symptoms 

The performance and safety of the vehicle might be negatively impacted by several symptoms brought on by a defective sensor. The common wheel speed sensor symptoms include: 

ABS Light on:  

When a vehicle speed sensor fails, the typical sign is that the ABS light comes on. 

Speedometer Malfunctioning:  

If the speed sensor fails, the speedometer may vary or cease operating entirely. 

Turn Signal and Traction Control on:  

Like anti-lock brakes (ABS) monitor wheel speed, traction control does the same. A malfunctioning sensor might activate the traction control warning light. 

Rough Idling or Stalling:  

The ECM uses the sensor to adjust timing and fuel injection. A faulty sensor may lead to engine stalling or jerky operation. 

Poor Fuel Economy  

If the ECM gets a false reading from a defective wheel sensor, the car will not get good gas mileage. 

These are some of the most important faulty speed sensor symptoms that you can detect on your own. After detecting these problems you should take your vehicle to a professional mechanic who can decide whether it needs repair or replacement. 

Wheel Speed Sensor Replacement 

A professional technician should examine your car if you notice any problems. A defective sensor might endanger the driver and the vehicle. The replacement process involves the following steps:

Figure Out What’s Wrong:  

The technician will check the ABS or ECM using a diagnostic tool to see whether an error code is saved there. This code will identify a defective speed sensor. 

Find the Sensor: 

In most cases, the malfunctioning sensor will be found close to the wheel hub. The sensor can only be reached once the technician removes the wheel and brakes. 

Replace the Sensor:  

To get rid of a worn-out sensor, disconnect its wires and unscrew its bolt. After making the necessary electrical connections, the new sensor is mounted. 

Test the System:  

After installing the replacement sensor, the technician will check the functionality of the ABS and traction control systems. 

Wheel Speed Sensor Replacement Cost 

Its replacement costs may vary by vehicle type, model, and sensor location. Typically, the price per sensor might be anywhere from $100 to $300. There may be an additional hourly fee of $100 to $200 due to labour. 

Wheel Speed Sensor Cost: 

Its repairing costs may range from free to several hundred dollars, depending on your vehicle’s make and model, the sensor’s location, and the new part’s brand and quality. 

A single-wheel speed sensor may cost anywhere from $50 to $250, with some high-end models going for as much as $500. Installation labour prices may also differ based on the mechanic’s hourly rate and the job’s difficulty. 

Wheel Speed Sensor Types 

There are two main types of wheel speed sensors: magnetic and hall-effect sensors. 

Magnetic Sensors:  

These sensors create an alternating current using a magnet and a coil of wire. They are more widespread and less expensive than hall-effect sensors, although they are susceptible to the effects of magnetic interference. 

Hall-effect Sensors:  

These sensors measure the magnetic field created by the wheel using a semiconductor. They are more costly than magnetic sensors but more accurate and reliable. 

Wheel Speed Sensor Location 

These are sometimes in different places from vehicle to vehicle. The sensor is often installed within or outside the brake rotor, close to the wheel hub assembly. The sensor could be part of the wheel bearing assembly in certain cars. 

Owner’s and service manuals might help you find the sensor in your car. Only try to diagnose or fix your car if you are a trained professional. 

Related Article: How to Find The Ford Transmission Speed Sensor Location? 

Wheel Speed Sensor Datasheet 

The manufacturer’s datasheet should be consulted before obtaining a replacement wheel sensor. Important details regarding the sensor’s sensitivity, frequency response, and working temperature range are included in this datasheet. 

Selecting a sensor that is compatible with your car and up to original equipment manufacturer standards is crucial. If you install a sensor without checking the specs beforehand, you might endanger the safety of your car. 

Wheel Speed Sensor Code: 

A malfunction in the vehicle’s speed sensors will cause the anti-lock braking system (ABS) warning light to illuminate. The ABS error code database stores information that might help diagnose the problem. 

Codes like “C1234 – Right Front Wheel Speed Sensor Circuit” indicate a problem with the right front wheel speed sensor or its associated wiring. A skilled technician can determine the cause of the malfunction by analyzing the diagnostic code. 


What is a wheel speed sensor? 

It is a gadget that can detect how quickly a car’s or truck’s wheels turn. Common applications include anti-lock braking systems (ABS) and traction control systems (TCS), which keep a vehicle from skidding by adjusting the brakes and throttle.  

How to tell which wheel speed sensor is bad? 

If you think one of your wheel speed sensors is malfunctioning, here are some important points: Brake irregularities, squeaky brakes, traction control, and an ABS warning light are all bad speed sensor symptoms.  

What happens when a wheel speed sensor goes bad? 

Braking and stability control problems might arise from a faulty wheelspeed sensor. To maintain the safety and dependability of your vehicle, a professional technician should be consulted if you suspect a faulty wheelspeed sensor. 

How to test the wheel speed sensor? 

Using a diagnostic tool, measuring the sensor’s resistance or output voltage with a multimeter, physically evaluating it for damage, and switching it out with a known good sensor are all viable options for testing a wheelspeed sensor. However, for reliable results, a professional mechanic should conduct the inspection. 

What causes wheel speed sensor failure? 

Many things can go wrong with a wheelspeed sensor, such as a buildup of dirt and debris, regular use and wear and tear, electrical problems, physical damage, fluid leaks, bad installation, or even factory defects. 

Can wheel speed sensors affect transmission? 

A vehicle’s gearbox is usually immune to the effects of a defective wheelspeed sensor. The transmission may not shift correctly or go into fail-safe mode if the vehicle’s speed sensor is not separated from the transmission speed sensor. 

What does a wheel speed sensor do? 

The speed sensor detects the magnetic field produced by a toothed ring on the wheel hub or a toothed tone ring on the axle. The information is then converted into an electrical signal for the vehicle’s onboard computer to regulate the braking or traction control systems. 


A wheelspeed sensor is essential in contemporary automobiles; they ensure the car doesn’t spin out of control when applying the brakes suddenly. Your vehicle’s safety and performance might be at risk if you wait to identify a broken sensor. 

This article gives you all the information you need to know about wheel speed sensors, such as including their datasheet, code, location, symptoms, and replacement options. With this knowledge, you can make informed decisions about your car’s braking and traction control systems, crucial to its safe operation.

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