I just replaced the L/F wheel bearing on my 2006 X-Type. The ABS sensor unplugged with no difficulty, and the tone ring came off easily also.


After installing the new bearing, and reassembling the car, it will now only drive about fifty feet, before the ABS starts "Chattering" (it can be felt in the brake pedal also), and the brakes "lock on" and the car won't move. The ABS warning light does not come on, although I know the light works.


It's necessary to shut off the ignition, then restart the car, but again, it will only travel about fifty feet before "locking on" again.


Any thoughts, suggestions, and/or advice will be most welcome.

 

I've moved your post from General Tech Help to X-Type forum. This is the place to post technical questions about your model.

Graham

 

Can you clarify a little bit? The X-Type front hub does not have a 'tone ring' as you call it. The signaling device for that ABS sensor is integral to the hub bearing. It's not something you can see.
Is it not the front you replaced, or not an X-Type??

 

Sorry about the confusion. One shouldn't post questions after a couple of Single Malts.
It is an '06 X-Type and my problem is with the L/F wheel bearing replacement. I had also replaced the R/R bearing and half-shaft on the weekend, so I was confusing the two jobs (with the help of the Scotch).


The job at the rear of the car went fine and there was no problem with the ABS afterwards.


However, after replacing the front bearing, which went smoothly, the ABS starts to "operate", to the point where the brakes "lock up". The ABS warning light does not come on, and only by shutting the car off, and re-starting will the brakes be released (temporarily).


Removing the 5 amp fuse for the ABS, will prevent "lock up" of the brakes , but of course there is no active ABS, DSC, or Cruise Control, and the warning Light is on.


Is it possible that having replaced only the one bearing, I've created an "imbalance" in the ABS sensor readings between the old and new bearings?

 

I do not think the car has any imbalance (but the scotch may give you some

Inside of the the bearing are a number of magnets. They are what the sensor see. I think that they need to be in the out orientation. I am sure there is a video on installing them. I would check this.

 

My vote would be the bearing is installed backwards. No signal on the the side that needs it. The abs is seeing a locked wheel.

 

Yes, installing the bearing backwards will cause ABS/DSC warnings and deactivate the systems. But you have a brake system that is activating, as though a wheel is spinning or locking up. Since you said you also did a rear bearing, I think you should look there.

My suggestion is to remove the wheel at the new rear bearing, remove that wheel speed sensor so you can look in at the reluctor on the drive axle. It should look sort of like a ladder. Slowly turn the axle while watching the 'ladder'. I think you will see a break in the reluctor ring at some point. That makes a jump in the signal to the ABS, and sets it off because it thinks that wheel speed changes compared to the others.

If you don't find anything there, check the other rear reluctor. It could also be broken on that side.

Cheers,

 

Thanks for the thoughts.


I am quite certain that the bearing is not in backwards, and I am even more certain that the problem does not come from the rear. In either case, the ABS warning light would be illuminated, ....and it is not!


I know that the warning light works, since having removed the Fuse for the ABS system, has illuminated the light.


I'm leaning towards a defective, or even incorrect, new bearing. I've ordered another new one, and will try replacement as a cure.


I'll post results when available.


Thanks again.

 

Have it your way, but you are missing my point.

Yes, a reversed bearing in front would cause a warning light. That's because the result is a MISSING SIGNAL from that speed sensor.

The scenario in the rear I gave you, will not set a warning lamp. It will only cause an erroneous ABS/DSC brake activation. Which is your complaint. A split reluctor causes a CHANGE in the wheel SPEED SIGNAL, not a loss, and the system interprets it as a wheel slip or wheel lock up. The speed signal is there, it's just uneven. Therefore, the ABS thinks it's just doing it's job........ no warning light.

I should also add that being a 2004 and later car, different tire circumference can also cause a similar activation. For instance, a brand new tire on one side and a worn out tire on the other side; or different sized tires on the car.

Good luck!

 

If there is a problem with the ABS, then a fault should be logged in the module. Datalogger can watch all the wheel speed sensors and you can see in real time, the speed of each.

Reading the fault codes (C codes, CHASSIS codes) if present, might speed up a diagnosis. You will need dealer level diagnostics but throwing parts at a car might be more expensive than paying for a scan of ALL the modules.

bob

 

Hey XR Guy,


I really dislike, and always have, people who ask for an opinion, and then argue against that opinion. That's why I would never do that, and have not been trying to do that I really appreciate all the advice and opinions provided.


Obviously I didn't state my problem clearly enough.


After replacing the rear bearing I drove the car about 200 KMs, with no problem, other than the "howling" from the front bearing, It's only after replacing the front bearing that this problem showed up.


I've pulled the spindle again, and double checked the correct installation and direction of the new bearing. It is in correctly and the sensor appears to be fine


I cannot understand why the ABS warning light is NOT illuminated, even though there is an obvious problem.


I'm going to replace the sensor as a "just in case" measure, but I still think that a defective sensor would illuminate the warning light.


With the fuse for the ABS system removed the car is driveable, and is not used in bad weather, so it's not a major concern, with the exception of having no Cruise Control or Stability Control. At least I can use the car while trying to resolve the problem.

 

Do you check the speed sensor? It might be broke or not fully insert, because it sense difference speed in difference side and activated the ABS, and since the wheels continue to rolling so it would locked up the brakes.

 

Got it!
If that's the case, then you need to find what must be messing with a wheel sensor signal, rather than find a missing signal. That is about the only way this could be happening and NOT throw a warning light or message. Something is making it think a wheel is slipping so it activates the ABS or Stability Control.

Might need to find a shop that has equipment that can datalog wheel speed sensors and compare all four at once.

 

Before you bring the car to the shop, remove the wheels to see which wheel sensor is bad, it's inside the nuckle close to the wheel bearing.

 

bob

 

Jus' backin' you up, Bob. Jus' backin' you up!

 

I know!!! We both had the same idea.

If I had this problem this is how I would diagnose.

bob

 

Thanks to all for the advice, comments and suggestions.
I'm going to have the car towed to a Jag service dealer and see what they find. I'll report their findings here, afterwards.

 

Hey All who responded,


Thanks again for the input.


Well, unfortunately I was incorrect about making the car at least driveable by removing the fuse for the ABS. That also causes a `Gearbox Fault, and a couple of other fault codes, which put the car in "limp mode" and undriveable. Compound this with the fact that the closest Jag service facility (35 miles away) cannot look at the car for a minimum of three weeks, and you can imagine my frustration.


So, as a "hail Mary" play, I chose to replace the new wheel bearing with another new wheel bearing. The same supplier, the same bearing manufacturer, and the problem was resolved.


The fact that the first new bearing was destroyed by the removal process, which means no refund, is not easily swallowed, but at least the car is back to normal.


I still cannot understand how an ABS problem, didn't turn on the ABS Warning Light, but I guess I'll have to live with that bit of unknown knowledge.


Once again, I thank all those contributors who offered advice and suggestions.

 

Now that we know, I can pretty much tell you what happened, I just can't tell you necessarily how.

Either that bearing was mis-built, or you inadvertently damaged it on installation and didn't realize it. The seal on one side of the bearing has several itty-bitty magnets evenly spaced around it. They are what trigger the sensor. I ran into one many years ago that was mis-built, with the magnets UNEVENLY spaced. By the same token, if that seal is poked or pushed in slightly somewhere on installation, one or more of the magnets will be a greater distance from the sensor than the others. That makes for an UNEVEN signal out of the sensor.

A wheel slip or near lock up results in an UNEVEN signal out of the sensor. The ABS does not know the difference. To the system, that's not a PROBLEM, that is something to ACT ON.

I'm sure yours was acting on an uneven signal. You just don't know exactly what the cause was.

Glad you're back on the road!