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Only started this morning!! Had car since 19/04/06 (last Wed).
when I'm braking and bringing the car to halt, usually starts around 15mph or less, the ABS seems to be kicking in and making the brake peddal bounce. Yet the car stops fine, with no overrun (lack of brake force)

If the ABS rings were worn, surely this would activate the ABS at any speed due to the ecu not being able to dertermine if the wheels are moving or stationary??

Again, if the sensors were dirty, this would have the same effect as above as it cant read the teeth clearly??

Any thoughts or ideas on where to start looking?

Hope its nothing too serious!

Cheers in advance, Dan

Hi mate i am a factory trained nissan hi-tech (but now moved to mercedes) i used to see this exact fault all the time on primera,s. It was caused by a break in the abs ring, the abs reads the teeth as a square wave just like on and off and it knows the frequency between on and off regardless of speed when a ring breaks it throws this frequency out and trips the system up, i could get primeras to do it by going over speed bumps without even pressing the brake you would get the familiar abs noise as it operated, new rings fix the fault

It could also be a lislodged sensor or dirt on the sensor ring.

Trying to remove the ABS sensors now, but does anyone know how to remove them??

Dan

With great difficulty!!
They are push fit.
When checking the abs ring i would take the driveshaft out!

taking the drive shaft out is a doddle, there's only 2 bolts, the hub bolt which requires a 14mm allen key and a bolt at the top of the suspension that requires an 18mm socket and holds 2 ball joints in place, you can then swing the hub unit out of the way and withdraw the shaft. there's a seperate post somewhere with more detail regarding changing cv joints.

Ok.
which corner shall i start at? The front discs look relatively new....so may start with front wheels?
Vag-com isnt showing any fualts with ABS...just my EGT sensor 1??? is that on bank 1 then? if so, which side is bank 1?

same problem with my car any idea how much new rings are

I had a similar problem recently and posted a thread here looking for help a few weeks back as it has been driving me mad. My symptoms were exactly the same but its finally sorted after a few trips to various garages. I had a crack in one of the ABS rings but in order to check this they had to remove the ABS sensors on each of the wheels. Unfortunately this meant breaking all 4 of them as they are so difficult to get out and each one needed checking, they then discovered a crack in one of the rings and I also needed a replacement driveshaft. The guy at the garage showed me the problem and is looked exactly as scorchio describes.

Glad to say its finally sorted, wasnt cheap though !

It's a simple job ,
1/jack up & support the car .
2/remove a wheel .
3/loosen the large bolt that is in the centre of the drive shaft.
4/as the bolt is loose you can push the end of it in , this will move the cv away from the hub .
5/use a light and look at the abs ring that sits on the cv joint , spin the shaft so you can see the whole of the ring .

The ring should not have any breaks or be loose . Start with the front's .
good luck
ps i've got spare shaft if any needed . g

I've got the same problem! At least I know what I'm up against now.

Thanks to all who have posted help.

Hi, I've got the same problem. Split ABS Ring on the O/S/R. Anybody know if this is available as a part on its own or have a part number?

Yep ... after a race down the M1 at silly hours with an M5 one of my rear rings decided to part....
Spent the next days listening with amusement to my noisy ring !!!!! exactly .... it got replaced at a cost of £100 from euro car parts ---- whole joint kit, cant get rings seperately.. correct me if im wrong, but its not much too pay when your brake pedal kicks back at 70+mph .... not just slow speeds...
it progresses after a few days ....
if you look at your old ring.. it will be all brown, soft and oxidised ...

Took about 45 mins to change out, as posted above ... remove centre bolt, wheel, top arm front bolt, pull it forward and push the joint out the back, cut the old boot off, hold the shaft & <beep> the joint towards you with a large persuader ... its off, fit the new one in reverse without twating it ......
Enjoy ......