ABS

Paul_Humphreys

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I know there is a way to test them, but I do not have the right tools.

Has anyone gota spare sensor I could borrow? I think one of mine is playing up and I want to find out the problem one, if there is one.

Paul
 

Rob

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You don't need any tools to check the sensors. All you need to do is short out a couple of terminals in the inspection port and read the "Morse code" of the dash. Its all in one of the FSMs.
 

Jon Wildsmith

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A faulty sensor doesn't always trigger a fault condition with the ECU Rob. I think one of the most common problems is a weak signal which gets worse at slow speeds and so as the vehicle is coming to a halt the ECU thinks one wheel has locked up and it's responce causes it to pull to one side. Don't know what Paul's symptoms are though?
 

Chris

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That's precisely what mines does Jon - but not every time. And sometimes the ABS light does come on until the ign is reset. The spare sensor that I got some while ago is clearly lacking in magnetic strength and needs replacing. I really don't think that it's anything more complicated than that - this time. Tried other sensors on the other wheels and they will pick up quite a load (carefully of course) but the OSF is weak.

Chris
 
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Paul_Humphreys

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Jon Wildsmith said:
A faulty sensor doesn't always trigger a fault condition with the ECU Rob. I think one of the most common problems is a weak signal which gets worse at slow speeds and so as the vehicle is coming to a halt the ECU thinks one wheel has locked up and it's responce causes it to pull to one side. Don't know what Paul's symptoms are though?


That is just what it is doing Jon. It pulls to the left a little and does it about 7-8mph. I am sure it is the drivers side front sensor that is the problem. I just want to make sure it is a sensor that is the problem before I go putting lots of money into it.

Paul
 

Chas

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Paul_Humphreys said:
[quote="Jon Wildsmith":gjzpfm1g]A faulty sensor doesn't always trigger a fault condition with the ECU Rob. I think one of the most common problems is a weak signal which gets worse at slow speeds and so as the vehicle is coming to a halt the ECU thinks one wheel has locked up and it's responce causes it to pull to one side. Don't know what Paul's symptoms are though?
It pulls to the left a little and does it about 7-8mph. I am sure it is the drivers side front sensor that is the problem. Paul[/quote:gjzpfm1g]
I had my brakes pulling slightly to the left at slow speeds which I originally thought was a sensor problem, turned out to be a warped disc, whether that was the sole cause or not I don't know, but after the discs were changed the pulling went away.
Chas
 

Paul_Humphreys

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Discs changed last year, after the pulling started. I put it down to a sensor as I can feel the ABS working at the time.

Paul
 

Jon Wildsmith

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can't you swap the sensors side to side and see what happens? I'm assuming you hear / feel the ABS pulsing when it pulls?
 

Andy Harvey

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Paul.

Had the same thing on mine and eventually (after 4 years of driving with ABS switched off) replaced the faulty sensor. Simple way to at least check the basics is to pull it out and check if it is still magnetic. The one on the good side was considerably more magnetic than the one on the bad side - just took a sheet of thin card between it and the metal to stop the attraction. The good one still stuck. I know that is a really binary and not at all technical way of checking but it at least identified the faulty part. When I put the new (second hand) one on, the magnetism on both was pretty much the same - again by feel not by anything techy.
 

Paul_Humphreys

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Thanks Andy. Might just ask Stef for another anyway s when it is out I can change it.

Paul
 

pugwash

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Hey Paul,

If you end up having to buy a pair then i'll go halves with you- one of mine is buggered too

thanks

James
 

Gav Peter

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I can confirm that & he has them in stock at present (or did have last week when I was struggling with my ABS)

Turned out that mine was a rear one that was faulty but he ain't got them in at the moment...

Farkin expensive items...
 

pugwash

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anyone know what sort of money you are talking for single ones?
 

Chris

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Wayhay...

Well, after lots of swapping and piddling around making the fault better, worse and move around, I finally hit on the idea of removing that thin shim that's crimped onto the body of the sensor. I did check to see that the tip didn't foul the rotor before someone suggests that.

Whaddy know?? It worked. ABS judder all gone, brakes working perfectly. For now I suppose. The sensors seemed to have plenty of magnetism in them. You could pick up a spanner on them. But they juddered at walking speed when pulling up. Well not anymore matey-boy. That gives me time to save up for a pair of new ones in about 2012.

Chris
 

Paul_Humphreys

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Not had a chance to look at mine yet. But you could have a point Chris. As I run after market CV, it could be that they are not close enought to the sensor to provide a proper pick up.

Paul
 

Chris

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Maybe Paul. I know that Mr T fitted them to the part, so why take them off, but WHY did Mr T fit them? They are an extra component, extra fitting, extra design etc etc. And they are so simple to pull off. It begs the question as to whether they really are supposed to be an adjustment. The later black plastic ones (Ian lent me one) don't have the removable metal shim, but do have it as part of the injection moulding. Why? You can see it clearly there replicating the old original metal shim. Maybe you can file it off. I dunno. Seems odd to me Grommet. :character-grommit:

Chris
 

Dave 2000

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Adding to ABS woes the bronze bushing in the front spindles can wear, add this to some wear in the flange/CV and the CV can run out of true moving the sensor ring in and out of sensor range, the ABS sensor no longer 'seeing' the ring while other sensors are reporting back ok triggers the ABS as it assumes the wheel is locked.

regards

Dave
 
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