How Do I Know Which Wheel Speed Sensor Is Bad? How To Tell Which Abs Sensor Is Bad? new for 2022

How Do I Know Which Wheel Speed Sensor Is Bad?

How to determine which wheel speed sensor is bad? An ABS sensor is a tachometer that measures the speed of a wheel and transmits this data to the ABS control unit. The control unit uses this information to determine whether one or more wheels are locking up and about to skid. If the control unit identifies a skid, it activates the ABS system, which pulses the brakes on and off very quickly. This prevents wheels from locking up and the vehicle from skidding.

The best way to determine if an ABS sensor is dysfunctional is by scanning the car for codes. Oftentimes, these codes will start with the letter C. Luckily, if you have a code reader or scanner, you can connect it to the OBD-II port and check for anycodes that point to a failed speed sensor.

Test With Voltmeter

After you’ve found your first ABS sensor, carefully remove the connections from it. The voltmeter probes can then be clamped to the ABS sensor connection. It’s a good idea to use a voltmeter with clamps because hand holding the sensors on the ABS sensor might be difficult.

After you’ve connected the voltmeter, turn it on and set it to AC or alternating current. It’s critical that the probes aren’t touching when testing; otherwise, the reading will be incorrect. The voltmeter should drop to a value of zero once turned on. The system is now ready for testing when the voltmeter reads 0 volts.

All you have to do to test the ABS sensor is spin the wheel hub with your hand. It’s critical to go slowly when doing so. A charge will be created when you spin the hub, and this will result in a voltmeter reading. The reading will be around 400 AC voltage if the sensor is operating correctly. The value will fluctuate based on how rapidly you spin the rim and depends on the car.

Test With Multimeter

If you don’t have access to a multimeter, you may test the ABS sensor for functionality. To do so, remove the ABS sensor from the vehicle and connect the multimeter leads to the sensor terminals. When the sensor is operating correctly, it should produce a reading of around 0.45-0.55 volts. If the reading is higher than this or lower than this, there’s a good chance that the sensor is damaged and must be replaced.

Test With Magnet

You can test the ABS sensor by placing a magnet on the tip of the sensor. If the light on your dash comes on, then the sensor is working properly. If not, it’s likely defective and will need to be replaced.

Test With Ohm Meter

To check an ABS sensor with an ohmmeter, you must first remove it from the vehicle and attach it to the meter. You’ll then need to verify the sensor’s resistance. If the resistance is too high or low, it’s probable that the sensor is faulty.

Tips when testing ABS Sensor

When attempting to discover the bad ABS sensor, it is typically easy to jack up the car and put it on jack stands. This way, you may remove all four wheels at once and test all of the sensors back-to-back.

You won’t have to keep lowering and raising the car to test various sensors and deal with removing and replacing tires. If you can get all four wheels off the ground at once, it will save you a lot of time hunting for the ABS sensor that is causing the problem.

If none of the sensors indicate a problem and you clean around all of them without any of them reading bad, then you should be safe to drive. If the ABS light comes on again when you replace the tires and there is no apparent reason for it, this indicates that there is still an issue with the system. The problem is most likely in the ABS system’s wiring, which can be difficult to detect but may be detected using a voltmeter set to ohms to measure resistance.

Keep the following things in mind when testing an ABS sensor:

• Before you begin, ensure that the power to the sensor is shut off.
• Inspect the wiring to see if any connections are loose or wires are frayed.
• Test the sensor with an ohmmeter or multimeter.

If the sensor is bad, you will have to replace it. Though replacing an ABS sensor isn’t too challenging, getting the right replacement sensor for your car matters.

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Symptoms of a Bad Wheel Speed Sensor

On the dashboard, the ABS Light is lighted

Because the wheel speed sensor also monitors your car’s anti-lock braking system, when the ABS Light illuminates, it’s often due to damaged, disconnected, or hit by debris. This indicates that you’ll have to replace the wheel speed sensor because other issues can cause this light to come on include a malfunctioning ABS pump, worn brake pads, low brake fluid levels, difficulties with brake pressure and air trapped in the brake lines.

If you notice the ABS Light on your dashboard lit as you drive, it’s critical to contact an expert mechanic as soon as possible due to the significance of brake component failure or damage.

ABS does not function correctly

The anti-lock braking system is designed to apply brake fluid evenly to the calipers and pads in order to slow down your car without locking up the tires. The wheel speed sensor is responsible for sending information about the wheel’s speed directly to the ECU, which then tells ABS how much pressure can be safely applied. When there’s an issue with the sensor, it alters ABS as well.

If you notice that your front tires lock up when you press the brakes, schedule a visit with your local ASE certified mechanic as soon as possible. This could be indicative of a larger problem and should not be ignored. If necessary, stop driving the vehicle until the ABS system can be properly diagnosed and fixed by a professional. In some cases, this may only require replacing a faulty wheel speed sensor.

The Traction Control Light is turned on

Most of the time, the Traction Control Light comes on in newer models when the driver decides to turn off that particular system. If you didn’t do that manually or if traction control is still active, then it’s probably because of a faulty wheel speed sensor. The wheel speed sensor also gets information about how fast the wheels are going and sends it to whoever is operating the traction control; so basically, this light coming on means that your wheel speed sensor is either worn out or broken.

Traction control, like the ABS system, is a safety feature for automobiles, trucks, and SUVs. It’s intended to guarantee that the tires don’t break loose when you apply the throttle. If you see that the traction control light is on despite the fact that you didn’t switch it off, get in touch with an ASE-certified technician right away.

How Do I Reset My ABS Sensor?

In order to reset the sensor, you must first find the ABS control module. It is typically placed under the hood, close to the battery. After finding it, you will need to disconnect the negative battery cable.

After the negative battery cable is removed, press and hold the brake pedal for 30 seconds. This will allow any residual pressure in the lines to be bled off. Once you’ve held the brake pedal for 30 seconds, you can reconnect the negative battery cable and start your car.

Read more How To Tell If Your Wheel Hub Is Bad? How to check your Wheel Hub Assemblies?

FAQs How Do I Know Which Wheel Speed Sensor Is Bad

How do you test a speed sensor?

In the repair manual for your car, remove the sensor from the housing and disconnect it. Remove the sensor’s wire connection. Connect the probes to the ground and reference wires in the connector with a multimeter’s voltmeter. The sensor is faulty if no voltage is received.

What will happen when a speed sensor goes bad?

A defective speed sensor cannot give correct speed readings. If this occurs, then the car’s computer system won’t be able to manage the gear changes in the transmission. This may cause the gears to switch faster and harder than what is normal.

Can you drive a car with a bad speed sensor?

In general, driving a vehicle with a broken wheel speed sensor is not recommended. Because the computer will be unable to determine the speed of your car, it may apply brakes more quickly than necessary or increase engine power.

How much is it to fix a speed sensor?

The cost of labor is estimated to be between $106 and $133, while the cost of parts is estimated to be between $144 and $162. This does not include taxes or fees, nor does it take into account your specific vehicle or location. You may also need other related repairs.