Technical After rear bearing change - ABS failure

[Deckchair5]

How far are the sensors from the magnet? 1 mm, 2mm or?
Who's going to know? Just close enough so you can pick up a constant signal

"I also couldn't find any adjustment off fittment off the sensors, ie I couldn't get them nearer or further from the magnet".
Probably aren't adjustable then

 

[Mal126]

Is it the right bearing, i.e for a.b.s, have seen bearings fitted that are non a.b.s., that is no magnetic fields in bearing so no signal to sensor.

 

[Deckchair5]

Lammy said earlier that
"The magnet ring attached to the bearing is fitted to the inside off the axle so the ABS sensor would detect it".

So we're assuming it's an ABS bearing but it's a fair point, a few non ABS bearings have been erronously fitted in the past. Don't know why, as all modern cars have ABS

 

[lammy1]

After an afternoon at the garage I found out the following.
Changed again a rear bearing no results.
There is some signal coming from the sensors but to weak.
I checked it with another MW from my friend.
Put on my old bearings and the signal was OK.

What to do next?
Change the sensors ?? I phoned Fiat and they didn't got any answer.
Right it now becomes difficult for me what to do next.

greetings
Frank

 

[Deckchair5]

"There is some signal coming from the sensors but to weak.
I checked it with another MW from my friend.
Put on my old bearings and the signal was OK."
I'm sorry I can't understand what you mean. You checked what and how?
Does the warning light come on straight away at start up or only after you start to drive?

What voltage do you have going INTO the sensor? A too low voltage would cause a problem

Normally to get a stronger/ consistent signal, you'd move the sensor closer to the pick up ring if possible

Is it both rear bearings producing weak/ erratic signal now?
What kind of voltages are at the output to the sensor with the wheel rotating?

How is the brake pedal pressure now and the fluid level?

 

[Argonought]

Changed again a rear bearing no results.
There is some signal coming from the sensors but to weak.
I checked it with another MW from my friend.
Put on my old bearings and the signal was OK.

What to do next?
Frank

Logically at least, if the original bearings produce a good output but the replacement bearings produce a much weaker output (and assuming you've checked NumanR's post) then the only conclusion is that they're either the wrong ones or they're faulty!

 

[lammy1]

@ all

White smoke !!!!!!!!!!!!!!!!!!!!!!!!!
The problem with my ABS failure is a very simple one.
The bearing witch the dealer ordered was not good.
Altough the number on the bearing is the same as listed in the parts catalog.

It seems that you have to have the rear bearings for a 5-door Stilo.
They forwarded the question to FIAT and they came with another bearing after some ( 4 weeks) of investigation.
It seems that the bearing for a MW is the same as for a 5-door Stilo, different as stated in the parts catalog!!
The garage fitted them and hey presto, the ABS is functioning again.
And no ABS failure alarms.

greetings
Frank

 

[bozzy]

Great result Frank. Looks like you were up to the required "professional" standard then.