How To Tell Which Abs Sensor Is Bad: A Simple Guide!

Naomi O'Colman

How To Tell Which Abs Sensor Is Bad: A Simple Guide

How To Tell Which Abs Sensor Is Bad: A Simple Guide

An Anti-locking brake system (ABS) is an important system for your car. The ABS works with a sensor to detect wheel lock and prevent any tire from locking up. This sensor is known as an ABS sensor.

In the event that one of your sensors should go bad, you will experience a warning light on your dashboard, or in some cases, no warning at all about the one bad sensor. So, how to tell which ABS sensor is bad? Is there any sign you can see and how to detect them? Let’s find out.

What Is an ABS Sensor?

The ABS sensor is a simple device that is used to detect the locking up of a tire by the anti-lock braking system. It works with a sensor hub that sends signals to the ABS control module. The control module manages the braking system and operates all of the sensors within it. The control module reads information from each sensor and compares it with preset values to decide whether or not the brakes should be applied.

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The ABS sensor is a simple device that can be replaced by anyone with very little mechanical knowledge required. The sensor has the following parts:

  • Sensing element
  • Antenna
  • MAG (Magnetic Activated Generator) circuit.

It is not necessary to replace an entire ABS sensor if it isn’t broken, but only its sensing elements are bad. This is because the antenna and MAG are connected to each other with thin wires, so if one of them fails, the other will fail too in time.

Where is ABS in your car?

  • ABS sensors are located on both the front and the rear axles.
  • The ABS sensor kit is installed directly on the brake caliper. The sensor itself is fixed to a steel plate with two bolts.
  • The ABS sensor kit is installed directly on the brake caliper’s mounting bracket, which is located between the tire and disc brakes on each side of the car. When installing an ABS sensor, it must be placed so that its axis of rotation is equidistant from the front wheels and rear wheels of your car.

How to Tell Which ABS Sensor Is Bad in a Few Easy Steps

Method 1: Check the ABS Warning Light

The ABS warning light is a warning mechanism that indicates a problem with an ABS sensor. If you have this warning light on your dashboard, it means that there is a problem with one or more of your sensors. You will have to find out which one by following the steps below:

  • Step 1: Start the car and turn off its engine. Don’t do a test drive because it can cause further damage to your tire and other parts.
  • Step 2: Remove the wheel of a wheel that is not broken to find out which ABS sensor is bad.
  • Step 3: Check for a broken wire from the sensor. It is supposed to have two wires, if one of them has been cut or is missing, it means that you have a problem with the sensor itself.
  • Step 4: Then check for foreign substances on your tire and wheel, including oil, gasoline and so on. This can damage your tire faster than normal.
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Method 2: Check the Sensor Hub

  • The sensor hub has two colors. If you have a problem with it, it means that there are one or more broken wires in the sensor hub. The colors of the wires are brown and black.
  • First, remove all wheels from your car, but don’t forget to take off the brake pads because they could also be causing the problem. Then start up your car using only one front or rear wheel.


  • It is not advisable to use a jack to lift one of your wheels. Jacks can alter tire alignment. If you are not confident about handling this job by yourself, take it to a professional who is familiar with the ABS sensor system of your car.
  • The sensor hub is located in the front right corner of your car, which can be seen when your car is facing forward.
  • Startup your car using only one of the wheels. If the ABS light does not turn on, you don’t have a problem with your sensor hub. However, if it turns on, then you need to find out which sensor is faulty.
  • To check for broken wires in the hub of the ABS sensor, you will need some metal rods and some electrical tape. Only remove the broken wires (black and brown). Then use some electrical tape to fix all the remaining wires so they are not short-circuited.

Method 3: Using Multimeter or Voltmeter

Note: The use of a multimeter does not always indicate which ABS sensor is faulty. However, it might help you narrow down the problem so you can do further investigation to determine if your sensor is faulty.

  • Step 1 – Connect the positive probe of the multimeter or voltmeter to the ABS sensor. Then turn the multimeter on. It should read 0 now.
  • Step 2 – If your meter displays from 1.5 to 1.7, with constant reading, then the sensor is good. Otherwise, that sensor has a problem.
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Frequently Asked Questions

#1 How Much Does It Cost to Repair and Replace an Abs Sensor?

ABS wheel sensors cost anywhere from $100 to $200 each, while ABS control modules run from $200 up to $600 apiece. Discount prices are possible if you are not in a hurry.

#2 What Do I Do If My ABS Light Is On?

If your ABS light is on, the first thing to do is take your car for a test drive. This will tell you whether or not the light goes off during the drive. This way you will know if your system is working properly or not. It can also give you an idea of where the problem lies.

If your system is working correctly, and the light continues to stay on, you will have to disassemble your tire and wheel. The ABS sensor is located between rubber and steel, which means it can be damaged if the car is involved in an accident. This sensor is very sensitive and it can be broken at the slightest impact.

#3 Can You Drive With a Bad Abs Sensor?

A sensor is a device that gathers data. When it’s broken, the entire system can’t function because it needs the input from the sensor. While it is possible to drive with a faulty sensor, there are certain limitations imposed on the vehicle. This should be taken into account before taking the car for a test drive.


ABS sensors are simple devices that are easy to change. However, when one of them is broken, you will receive an ABS warning light. You can fix your car by yourself with the knowledge you have gained from this article. However, if you need any further help, take it to a professional mechanic who knows how to deal with ABS sensors in different cars. A good mechanic will come up with the best solution in no time at all.