Abs problem???

[Explorerfan87]

Just bought my first ford it's a 98 explorer Eddie Bauer edition. I love this vehicle drives great looks fantastic all in all I'm very impressed with the car. I do have an issue that's driving me insane. I'm a do it yourself kinda guy and I'm capable of taking on any job in my garage so any advice would be great
My issue is my abs is firing when I'm just coming to a stop ( doesn't happen all the time) anyways my abs lights not on so I know I can't scan for codes nor is my brake warning light on I've read threads of the wheel sensors could be the issue but I can only find 2 sensors and they look fine I cleaned some dust and grime off them and it seems to have helped but it still fires here and there. My brakes work fine there's no noises or grinding sounds when stopping... I've checked for leaks and could not find any all my brake lines are fine the master cylinder looks ok everything seems fine with the abs and brakes but in order to get a safety in my city they need to be in perfect working order if I need to provide any further information I will do my best but any help with this problem will be helpful at this point
Thanks

 

[bobflood]

If I'm not mistaken, I believe there is a single rear ABS sensor in the differential.

 

[drdoom]

That is a know problem, false abs activation. FORD wrote a TSB on it something to do with weak signals from the front sensors which I thought were changed in '98.

 

[Explorerfan87]

You say it's in the rear differential? I would have to take it apart to access the sensor? I will do some homework I guess to see if there is another way to get to it.
And I was under the same assumption that ford changed there sensors but I guess not the only thing I can think of is actually removing the sensors and testing them separately.. Would that even help me or am I wasting time? I would just buy new ones but I'm not about to start replacing parts only to find out it didn't help
I have noticed another issue if one at all but the rear differential when I remove the back wheels pop the caliper and rotor off I can actually pull on the driver or passenger side wheel assembly it shifts about half an inch maybe less could this be a reason for anything I don't feel any shifting when driving or turning and there's no vibration while driving on the highway is this normal in a ford or am I starting to discover more problems

 

[phil9475]

I had the exact same problem. There are three ABS sensors. One in each front hub and one in the rear differential. My scan tool can display the MPH from each sensor and they matched above four to five MPH but below that the fronts would go to zero while the car was still moving. Tap the brakes and the ABS fires. You can pull fuse number 7 in the power distribution box to shut off the ABS system but the dashlight will come on for the ABS. The RED brake light will not light. Depending on where you live this may or may not fail an inspection (perfectly legal in Massachusetts for the ABS light to be on during an inspection). I replaced my front sensors and the problem is gone. The part number is XL2Z-2C204-AA.

 

[radman]

Explorerfan,
It is normal to have some movement in/out of the axles. Half inch seems excessive to me, but the half moon key inside the diff is what controls Axel lateral movement.
The rear speed sensor is located on the top of the diff housing on the outside. It is held in with one bolt and has an "O" ring to keep the gear lube from leaking out. It is not hard to remove but can be a butt to get to.
I do not believe the rear speed sensor is your problem as it will set an anti-lock brake light on your dash if it is bad. Once it is removed you can check the ohm reading to prove if it is working or not.

 

[Explorerfan87]

Alright thanks for the help guys. Little weekend tinkering I should get this sorted out. I wish I could just pull the fuse and go that route but if my lights on then they won't issue a safety

 

[05explorer1974]

Ford part number is F85Z-2L373-AB I believe. This is a slight chance but I have the HCU and or the ECU go bad to. But chances are it's the diff sensor.

 

[Explorerfan87]

So I have tested all sensors with positive results from all of them
I am still having this issue and I'm stumped other then the abs unit itself being bad I am lost for ideas

 

[budwich]

your problem is likely one of the hubs... its got debris (likely bearing "dust") that is causing a poor sense of the speed that the hub is turning at especially slow/low. You can try blowing / vacuuming to see if it helps. Next stop, hub replacement.

PS. look at the subsequent thread in the list that "fixes" the issue by cleaning the bearing surface which appears to lift the sensor according to the poster.

 

[Explorerfan87]

Thanks budwich il try this out and check that thread out aswell