Can you clean a wheel speed sensor

I was getting the ABS warning light and DSC warning message intermittently. Also, sometimes when I would apply the brakes I could hear the ABS system clicking away even though I was nowhere near the limit of traction. Usually it happened when I was almost stopped and only going 5 to 10 miles per hour. Info from this forum told me that it was most likely either a dirty wheel speed sensor or a bad wheel speed sensor, so I decided to clean them all to see if that would fix the problem. Here is a tutorial with pictures in case anyone else wants to try this.

Tools needed:
* 5/16ths inch socket with a ratchet (a 5/16ths inch wrench will work, too)
* Toothbrush
* Dish soap.

Also, you need to take the wheels off. The tools for that are already in the trunk.

Time:
It took me about 90 minutes. If you have an impact wrench and a floor jack it will go faster, but I was just using the jack and lug wrench from the trunk.

Skill Level:
Your daughter could do it.

I did the front wheels first. Just jack up one wheel and take it off. I figured out after I had both front wheels finished that it would have been a little easier if I had turned the wheels in the direction of the wheel sensor I was trying to clean. In other words, when working on the left front wheel, turn the steering wheel to the left. When working on the right one turn the wheel to the right. Make sure you only turn the wheels when both front wheels are on the ground. You don't want the car falling off of the jack.

So here's the tutorial...

Removing and Replacing the Front Sensor

Here is a picture of the front right wheel well. The sensor is on the other side of the rotor and you can't see it in this picture (That's why I said to turn the wheel to the right. It would be easier to access the sensor with the wheel turned to the side.

Here is a picture of the actual sensor. You can see the little cog thingy on the left side of the picture. The sensor bolts on right next to the cog thingy. As the little cogs move past the sensor the sensor detects them and sends a signal back to the ABS system so that it knows the speed of each wheel. In this picture I have already removed the one bolt that holds the sensor in place. It's a 5/16ths inch bolt and it is very easy to access and remove.

By the way... you can see the tire on the right side of the picture because when I was a kid my dad taught me to slide the wheel under the car so that if the car falls off the jack it will still be supported by the wheel. Jack stands will do the same thing. It's just a little safety measure.

And this picture is from an angle you will never see unless you have the ability to remove your head. This is from within the wheel well looking back. The wheel speed sensor is nice and clean because I have already removed it and cleaned it. Once again, the bolt which holds it in place is not installed in this picture. You can see the bright, shiny brass where the bolt will be inserted. In this picture you can also see the wire harness which plugs into the sensor. Make sure you check the harness for damage.

Removing and Replacing the Rear Sensor

The rear sensor is even easier to get to than the front sensor. After removing the wheel you can easily see the sensor by sticking your head in the wheel well and looking down.

The rear sensor looks exactly the same as the front, except as I mentioned above, it mounts on a housing that hides the little cog thingy. I think that's why the rear sensors were dirtier than the front sensors. The front sensors get washed off any time the car goes through a puddle, but the rear sensors are protected from the elements. grease and other crud builds up on them and it doesn't get rinsed off. Here's a picture of the sensor after it has been removed. You can see the cog thingy through the little hole.

Cleaning the sensor

Here's one of the dirty sensors I removed. This one was the dirtiest, but both of the rear sensors were much dirtier than the front sensors. I think that's because the front sensors are exposed, and the rear sensors are buried in some kind of housing which surrounds the rear axles.

To clean the sensor, simply take it to the kitchen sink and scrub it with a toothbrush and some dish soap. Try not to get any water into the electrical connector end of it. If you do get water in there, it's not the end of the world. Just tap the water out and then wait for it to dry before you reinstall it. You don't want to reinstall it wet because you might end up with some corrosion in the connector.

After about 45 seconds with the toothbrush your sensor will end up looking like this:

And that's it! It's really a simple "repair". I've driven my XK8 about 50 miles in city traffic since I cleaned them and the ABS/DSC warnings haven't activated, and I haven't had the faulty clicking from the ABS system. Prior to cleaning the sensors I would have expected it to happen at least 3 or 4 times. Only time will tell if this actually fixed it, but judging by the amount of gunk on the rear sensors, I think dirty sensors were the culprit.

UPDATE!!! I just made a video on how to do this. You don't even need to remove your front wheels! The pictures above are still helpful because they will help you locate the front wheel speed sensors with your hands. You can't really see them because they are hidden by the tire and the front fender. The rear sensor are easy to see once you get the wheels off.

Here is the video:

Jaguar XK8 Wheel Speed Sensors - YouTube

Can a speed sensor get dirty?

How do you fix a wheel speed sensor?

What can damage a wheel speed sensor?