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ABS light on after Wheel Bearing Replacement

So I went to a mechanic recommended to me as I am new to the area. I needed my front right wheel bearing replaced. He called me up and said it’s done but they may have “bumped some wires or something” because the ABS light is on now. He wants to replace the sensor. My question is, is this a common mistake? I’ve had this repair done to vehicles in the past and this has never happened. I also just dropped around $400+ on this replacement. I’m not sure if I am willing to pay for someone’s mistake. What are other’s opinions? I just don’t know if it’s more common than I think.

I would point out to the mechanic that the ABS light was not on when you brought your car to him, and that you want it fixed. Suggest to him that if he wants to be compensated for fixing this, that he submit a claim to his garage keepers liability insurance carrier.

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Try, “Hey, you broke it? You fix it.”

Replacing wheel bearings today means you need to deal with the ABS sensors… and many reside right in the wheel bearing housing. Most often when someone loosens the hold down fastener…the fastener comes out as expected, then they try to pull out the plastic sensor that resides in a finely made hole and is a tight fit…after some water and salt and time…that hole closes up around that ABS sensor and its all over when a guy twists the sensor into two pieces.

If it was a wire “bump” then the wires continue to work…they don’t mind bumps too much as they live on the moving suspension…so they move and bump all day long.

The advice from my esteemed colleagues is solid advice… No ABS light on prior to job…so make it right, the details of how are between the tech and his employer, not you. Just like @old_mopar_guy said.

I had to replace the right front ABS sensor on my 1995 Toyota Avalon, when I got an ABS light on the dash. I had to drill the sensor out, (it was supposedly held in by one screw) as it was jammed into place. Before I put the new sensor in, I reamed the hole so as not to have a repeat performance. A year later, both wheel bearings needed to be replaced. Not a DIY job (at least for me). Mechanic said that he had to destroy the left front sensor to get it out-no problem with the right front.Turns out Toyota had a technical service bulletin addressing the problem of too-small a hole.

I dont doubt the veracity of that story @tom418 I’ve often wondered what the deal was between the hole and the sensor. Never seemed to be good enuf reason for the clearance to be so tight at least to me…

I try to avoid issues by using carefully applied Never Seize compound on the things if I ever remove one without breaking or installing a new one.

The problem is that everything is put together “naked” it seems these days. I mean cant anyone spare a dab of grease anymore? I think “Carl in Accounting” figured that by not dabbing grease anywhere he could save xx mfg 5.2 million across 10 years or something…yeah that’s it… that’s my story and I’m sticking to it.

I’m a Greasing and Never Seizing fool anymore…

It’s not unusual to run into ABS problems when replacing wheel bearings from the posts we get here. You might try the forum search feature, above right on this page, see who else has posted about this problem and what the resolutions were.

Good ideas above. Another that seems less likely, though still possible, is the wheel bearing replacement part isn’t compatible with your car’s ABS system.

As far as who should take the hit for resolving this problem, I’d say it depends on what the cause is found to be.

The sensor has to have a water tight seal. Otherwise, water could get at the bearings. Most I have seen use a small o-ring and a tight fitting hole.

Also bear in mind that the alignment and spacing to the reluctor wheel (tone ring) needs to very tight tolerance to ensure good signal level.

What I see happening to the ones I have extracted is that the sensor bore rusts above the o-ring, making it very difficult to extract so it pays to be uber patient twisting, rocking and lightly prying on it.

Once out, you really have to inspect that o-ring for damage being forced past the corrosion. They tend to mount the sensors near the top for ease of wire routing so the seal is very important to protect the bearings. Once cleaned up and regreased, they go in/out pretty easy.

My grievance is when I find security fasteners and rivets holding them in. One GM I R&R’d had a female penta head cap screw on one side and a rivet on the other…