ABS Bearing question

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ABS Bearing question

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Good morning Steve. The relevance of "pulling all relevant connectors" is that modern cars with electronic systems use low voltages (often around 5 volts) and very low currents (typically milliamps) to operate the sensors. Older cars had virtually no electronics - alternators and instrument panels had some inbuilt stuff for regulators etc but very little, in the way of electronics, was connected externally via wiring and connectors - and they operated, mostly, at battery voltage and several amps of current. Because of this relevantly "brutal" flow of electricity the current could "bully" it's way through slightly "dodgy" dirty connections. Electronic systems, because they flow such low currents, just don't have this "bullying" ability so can be stopped by even the smallest of imperfection in a connection. So, if you simply separate and remake a plugged connection the wiping action on the male and female parts of the connector of doing this can reestablish a good connection. Spraying a wee bit of cleaner (not something like "good old" WD40 but a dedicated electric cleaner - which WD40 also make) is helpful. Poor connections in older cars are very common so I usually start by doing this as it's quite a quick and non intrusive thing to do with very little risk of a "neanderthal" like me doing a lot of damage. My heart bleeds for you when you say you don't even know where to start - to this day I still experience that myself with electronics and, apart from tracing the wires back I don't have a simple answer for you. It's good to accept your limitations and call a halt before you ruin something expensive! Of course even when you find the plug it's often protected from accidental disconnection by a locking device of some sort. Most consist of a wee lever that has to be depressed or a small plastic slider that has to be slid to one side, but some can be fiendishly difficult to figure out how they function and can be easily broken if you get violent with them. Then you find you can't buy just the plug because it's only supplied with the complete loom! A dirty day in the scrap yard usually results! This problem now seems to have been replicated by the designers of fuel line connectors where they connect to fuel filters. Previously the connection would often be a jubilee type screw clip on a short length of rubber hose. Quite simple to fix if something goes "wrong". Now though, they have these rather brittle plastic connectors which are released by pushing in a wee button like "thingy" on the side of the connector. They are sometimes very difficult to release and you have to apply considerable force to the "button" which is when the damage gets done. Then you find the connector is not available on it's own and you have to buy a complete fuel line to get it.

I think you've probably done as much as you reasonably can with the knowledge and ability level you seem to have? and I applaud you for your efforts. Generally our wee Fiats, especially the older ones, are not exactly at the "cutting edge" of automotive technology so most competent indy workshops should be able to sort this out for you and if they specialize in Italian cars that would be the ideal solution. The problem, of course, is finding that garage. Try googling "Fiat specialists Northampton" I just did and a couple of promising looking indies popped up. Even better would be to get a personal recommendation or for someone on the forum to be able to make a recommendation (make a separate post in the "leisure lounge" or "garages" section so we all see it). If you feel bold enough, I've actually hung around the main dealer workshop doors until a mechanic walks out and, very politely, asked his help - as to whether he might know of a colleague or an independent specialist garage who could help. Sometimes you'll be rebuffed and you have to be thick skinned enough to take some rude language! but I've had considerable success with this approach in the past and it could be worth trying if you feel up to it.

Oh, and the "copa slip" thing was about what anti squeal/ anti seize paste you use when rebuilding brakes. Us "oldies" were taught to use high melting point grease with ground copper diffused in it. The typical market leader in those days was a product called Copaslip https://www.ebay.co.uk/itm/251833861047 many other companies now produce similar product. Unfortunately, it was found that this product could cause problems with contaminating ABS sensors and corrupting their function - in fairness this was usually because some careless person had slapped far to much of the product all over the place. I've used it all my life, including when I actually earned my living on the shop floor, and never had a problem with it. However it's also true to say that it tends to dry out after a while and not do it's job so well, can also cause an electrolytic reaction between different metals due to the copper content, so, some years ago now, the general recommendation was made that Ceramic high melting point product should be used. I had rather varying success with this stuff until I discovered The Granville product https://www.thompsonsltd.co.uk/prod...gh0y1JbJtT7Plr-w2e1ptsf4i7X8Q_5xoCdDAQAvD_BwE being sold by my local motor factors, which I now use on all brake jobs. I still find the copaslip very useful for certain, brake unrelated, jobs though and still have a tin of it in my lubes cupboard. I asked the question because I'm interested in whether most people are now using a ceramic based product or sticking with the "good old" copper product.
 
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I forgot to mention above that I also smear this product: https://www.autoelectricsupplies.co.uk/product/827/category/154 on all my electronics connectors when I've had them apart. Can't really say how good it is but I've had no subsequent problems with connectors I've treated in this way. If you make and separate the connector a few times after applying the product, it distributes it around the rubber lip seals and seems to do a particularly good job of moisture proofing.
 
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The Bravo and Marea parts are usually now in 'clearance corner'

So speak to a couple of local 'mobile mechanics' about the bearing change job

The new brake parts can be refitted easily upon reassembly

The parts will probably be less than £80 all in

The fact it is reading 'SOME' wheel rotation does confuse me though..
 
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Brim987

Brim987

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Good morning Steve. The relevance of "pulling all relevant connectors" is that modern cars with electronic systems use low voltages (often around 5 volts) and very low currents (typically milliamps) to operate the sensors. Older cars had virtually no electronics - alternators and instrument panels had some inbuilt stuff for regulators etc but very little, in the way of electronics, was connected externally via wiring and connectors - and they operated, mostly, at battery voltage and several amps of current. Because of this relevantly "brutal" flow of electricity the current could "bully" it's way through slightly "dodgy" dirty connections. Electronic systems, because they flow such low currents, just don't have this "bullying" ability so can be stopped by even the smallest of imperfection in a connection. So, if you simply separate and remake a plugged connection the wiping action on the male and female parts of the connector of doing this can reestablish a good connection. Spraying a wee bit of cleaner (not something like "good old" WD40 but a dedicated electric cleaner - which WD40 also make) is helpful. Poor connections in older cars are very common so I usually start by doing this as it's quite a quick and non intrusive thing to do with very little risk of a "neanderthal" like me doing a lot of damage. My heart bleeds for you when you say you don't even know where to start - to this day I still experience that myself with electronics and, apart from tracing the wires back I don't have a simple answer for you. It's good to accept your limitations and call a halt before you ruin something expensive! Of course even when you find the plug it's often protected from accidental disconnection by a locking device of some sort. Most consist of a wee lever that has to be depressed or a small plastic slider that has to be slid to one side, but some can be fiendishly difficult to figure out how they function and can be easily broken if you get violent with them. Then you find you can't buy just the plug because it's only supplied with the complete loom! A dirty day in the scrap yard usually results! This problem now seems to have been replicated by the designers of fuel line connectors where they connect to fuel filters. Previously the connection would often be a jubilee type screw clip on a short length of rubber hose. Quite simple to fix if something goes "wrong". Now though, they have these rather brittle plastic connectors which are released by pushing in a wee button like "thingy" on the side of the connector. They are sometimes very difficult to release and you have to apply considerable force to the "button" which is when the damage gets done. Then you find the connector is not available on it's own and you have to buy a complete fuel line to get it.

I think you've probably done as much as you reasonably can with the knowledge and ability level you seem to have? and I applaud you for your efforts. Generally our wee Fiats, especially the older ones, are not exactly at the "cutting edge" of automotive technology so most competent indy workshops should be able to sort this out for you and if they specialize in Italian cars that would be the ideal solution. The problem, of course, is finding that garage. Try googling "Fiat specialists Northampton" I just did and a couple of promising looking indies popped up. Even better would be to get a personal recommendation or for someone on the forum to be able to make a recommendation (make a separate post in the "leisure lounge" or "garages" section so we all see it). If you feel bold enough, I've actually hung around the main dealer workshop doors until a mechanic walks out and, very politely, asked his help - as to whether he might know of a colleague or an independent specialist garage who could help. Sometimes you'll be rebuffed and you have to be thick skinned enough to take some rude language! but I've had considerable success with this approach in the past and it could be worth trying if you feel up to it.

Oh, and the "copa slip" thing was about what anti squeal/ anti seize paste you use when rebuilding brakes. Us "oldies" were taught to use high melting point grease with ground copper diffused in it. The typical market leader in those days was a product called Copaslip https://www.ebay.co.uk/itm/251833861047 many other companies now produce similar product. Unfortunately, it was found that this product could cause problems with contaminating ABS sensors and corrupting their function - in fairness this was usually because some careless person had slapped far to much of the product all over the place. I've used it all my life, including when I actually earned my living on the shop floor, and never had a problem with it. However it's also true to say that it tends to dry out after a while and not do it's job so well, can also cause an electrolytic reaction between different metals due to the copper content, so, some years ago now, the general recommendation was made that Ceramic high melting point product should be used. I had rather varying success with this stuff until I discovered The Granville product https://www.thompsonsltd.co.uk/prod...gh0y1JbJtT7Plr-w2e1ptsf4i7X8Q_5xoCdDAQAvD_BwE being sold by my local motor factors, which I now use on all brake jobs. I still find the copaslip very useful for certain, brake unrelated, jobs though and still have a tin of it in my lubes cupboard. I asked the question because I'm interested in whether most people are now using a ceramic based product or sticking with the "good old" copper product.
Interesting stuff. I do have some contact cleaner spray but it's the tracing bit that's tricky.

BTW, at the start of all this I did ring the Fiat main dealer, conversation follows:
ME: Hi, I'd like to order some Marea Parts please.
Fiat Dealer Spares Dept: A what?

Probably not even born when it was made, and it went downhill from there.
 
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Brim987

Brim987

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The Bravo and Marea parts are usually now in 'clearance corner'

So speak to a couple of local 'mobile mechanics' about the bearing change job

The new brake parts can be refitted easily upon reassembly

The parts will probably be less than £80 all in

The fact it is reading 'SOME' wheel rotation does confuse me though..
Clearance corner, tell that to fiat, nearly 400 quid for an injector. (but elsewhere hopefully...)

I've currently given on on the mobile mechanics, can't find any without awful reviews.

2 things remain: try the driving along live ABS graph (for fun) and book it in for OEM bearings and discs.

everything crossed...

Steve
 
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Interesting stuff. I do have some contact cleaner spray but it's the tracing bit that's tricky.

BTW, at the start of all this I did ring the Fiat main dealer, conversation follows:
ME: Hi, I'd like to order some Marea Parts please.
Fiat Dealer Spares Dept: A what?

Probably not even born when it was made, and it went downhill from there.
Yes, you're right, the tracing bit is tricky. I'm afraid I don't have any magic tricks and be careful what you do if you set your multimeter to Ohms when doing continuity checking as some electronics can be damaged by the current the meter will use to do this. Looking for Volts is pretty much full proof as the internal circuit resistance of the meter when set to volts is virtually infinite so it's almost impossible to do any damage when set on Voltage scales. Some meters have buzzers and some a wee light for checking continuity, same applies to them, don't try it, you may blow something unless you know exactly what you are doing.

I'd like to think not but I fear the spares situation you encountered with your approach to the dealer spares dept - where parts for older models are concerned - may only get worse under the Stellantis banner. I hope not, but I have little confidence. We can only hope that folk like those at Shop4parts will be able to keep us ticking over.
 
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Brim987

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OK, so here's the live data for all 4 speed sensors. Note the obvious spiky troughs on left front.

The bit that concerns me is that the brakes are horrible from starting (the pulsing, little actual braking).
Then they're fine once the ABS light is on and the system is turned off. (takes 20 seconds maybe)

Those spikes look like an occasional fault on the front left (dirt/damage etc???) but the braking behavior
seems to me to be more fitting to no signal (ie: skid) and the ABS refusing to allow the brakes on.

thoughts?

driving1.jpg
 
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Brim987

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Well, here's the news.... New discs,pads, both front bearings. 500 quid. Oooouch...
Nothing changed.
My boy is in bits, the clock is ticking down for mot day and the budget is blown, I was so sure that work would do it.

The graph looks exactly the same, with the occasional spikes down on front left sensor.

I've attached two driving graphs of wheel speeds and also one of just .. all the other things, the only thing showing there is voltage which seems a bit strange.

We've come so far, I've just got to save this thing and so I throw myself on the mercy of the forums, I'm out of ideas.

It's possibly a connection, but I have no idea where anything is or goes and I couldn't trace the wire.
That said, the occasional spike down (not off) doesn't fit with a connection break to my mind but what do I know?

Any thoughts appreciated - and I mean like desperately appreciated.

Thanks
Steve

errors.jpg
battery.jpg
abs2.jpg
abs1.jpg
 
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Thats frustrating isnt it..

But Im wondering how much time the fitter spent checking the sensors while it was apart.

How far are you from Oxford?
The garage that just fixed a friends long term problem are reasonable on price.
 
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Brim987

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Thats frustrating isnt it..

But Im wondering how much time the fitter spent checking the sensors while it was apart.

How far are you from Oxford?
The garage that just fixed a friends long term problem are reasonable on price.
51.8 miles from Oxford. Main issue is a restricted window of various school drops offs and collections which I can't miss or risk missing.

re: checking sensors.
All bearings and sensors are new, to be fair they weren't asked to investigate - I was sure the changes would fix it.

I can't get under the car to check wiring, even if I could - other than tracing and contact cleaner I don't know what else I could do,
(I don't have a wiring diagram, maybe I could find one but I'm too demoralised right now.)

There just has to be a clue in that spike downwards on the speed sensor in question. I've been googling away but haven't found anything similar yet. A transient break in the circuit would be a brief zero signal, perhaps that maps to a sharp spike down as the graph shows?. That said it seems far too reliable/frequent to be a random break. I don't know, I would give up but that means breaking my boy's heart.

Steve
 
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I'm getting out of my depth now with this but a thought has just occurred to me. You're obtaining these graphed out puts using MES, obviously. However there is one thing worth thinking about here and that is that MES displays what the ECU "thinks" it's seeing. By that I mean the ECU is "in between" the sensor and the computer screen. These graphs we see displayed by MES are not the same as you would get by using an automotive oscilloscope - like Pico for instance. The signal is quite possibly being "contaminated" by something going on in the ECU whereas an oscilloscope takes it's source signal directly from the sensor via back probing of connectors (or wherever you decide to back probe) but you can eliminate the the ECU from the process which you can't with MES. I'm not very sure where that gets us but maybe it'll spark off some thoughts from someone "brighter" than little old me?
 
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Brim987

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I'm getting out of my depth now with this but a thought has just occurred to me. You're obtaining these graphed out puts using MES, obviously. However there is one thing worth thinking about here and that is that MES displays what the ECU "thinks" it's seeing. By that I mean the ECU is "in between" the sensor and the computer screen. These graphs we see displayed by MES are not the same as you would get by using an automotive oscilloscope - like Pico for instance. The signal is quite possibly being "contaminated" by something going on in the ECU whereas an oscilloscope takes it's source signal directly from the sensor via back probing of connectors (or wherever you decide to back probe) but you can eliminate the the ECU from the process which you can't with MES. I'm not very sure where that gets us but maybe it'll spark off some thoughts from someone "brighter" than little old me?

Interesting idea. I actually have some old scopes in the garage but hope is fading here as I get more tired. I don't know how I could scope it sensibly while stationary... All sounds like a specialist job and they don't seem to exist.

I actually found http://fiatmareaclub.com/viewtopic.php?t=23249 (A czech marea fan club!) where it said:

C1245 Coil outlet valve ABS left rear Circuit short to ground so the ABS control unit - its coil or signal from the left rear wheel has a short circuit
(So left rear in their case, left front in mine).

Various other sites I researched pointed to chaffing of the cable which may well amount to a short..

The problem kinda gradually happened and got worse so that might fit with a cable deteriorating.. maybe.

I think the final final last gasp attempt would be to ask the local garage to check the cables when it's on a ramp but other than that
the lights are going dim....

This is just so very depressing, damn I tried.

Steve
 
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Oh I know the pain Steve! We tend to buy our cars at about 18 months old (my Ibiza was an exception which I bought new and it's "lost" me more money than any car I've owned simply via depreciation). Then we run them until it's not financially worth prolonging their agony! nearly always over 10 years but a couple - my old Cordoba diesel and the wee Panda Parade both in my avatar picture - for over 20 years. I tend to get very emotionally attached to the cars and, as I become truly familiar with their individual wee foibles, they become like old friends. Oh I lead such a "sad" life. I find it very difficult when the day comes that I have to say to myself "No, it's just not practical to try to weld that floor/sill up any more" or "That part costs how much? Oh deary me! - Time to say good bye" I was just thinking back and I can only remember two cars which were part exchanged (both belonged to my older boy whose's wife covers stellar annual mileages so needs something economical and reliable) otherwise the others have all been run until they were scrap value.
 
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Is the marea related to the Coupe in regard to these sensors?

That should field far more recent info on here.

There are bound to be a couple pf specialist Alfa workshops nearer than Oxford also ( Im still disappointed your last mechanic didnt offer further assistance)

Use the ePER service..and ebay to see what your system is related to :cool:
 
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Brim987

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Indeed, my wife is the opposite. She hates old cars (and spending money on them) ever since a mini's brakes failed in her youth.
So she gets to order a new Lexus and I get the Marea...
It's just a fact that most cars will lose you money, except my Capri turbo.
:)
I now expect that to blow up this week...

As an adult, the pain of loss is acceptable but in this case the car is my boy's link to his grandad.

I actually got a second wind last night and was up until 5am researching all this.
I found this link which might be worth a go:

Something else which could be a clue to somebody:
The mechanic noticed that the wipers kinda stuttered on the way back down - not sticking, definitely something electrical
and that momentary pause/confusion does look similar to the speed sensor dip spike. Maybe?
He said he cleaned up the earth point under the bonnet but it made no difference.

Steve
 
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I meant Coupe..

But still ePER will give you YOUR MAREA part numbers..and can help you research what else carries the same parts

If its in something more commonplace.. or still in circulation.. you will have more threads and information at hand.


As weve discovered MANY places are lost with the electrical side.. you need a different approach

Somebody who earnt a daily living with year 2000 Italians will have both the KIT and experience
 
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Brim987

Brim987

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I meant Coupe..

But still ePER will give you YOUR MAREA part numbers..and can help you research what else carries the same parts

If its in something more commonplace.. or still in circulation.. you will have more threads and information at hand.


As weve discovered MANY places are lost with the electrical side.. you need a different approach

Somebody who earnt a daily living with year 2000 Italians will have both the KIT and experience
ah the little turbo (sometimes) thing, yes I nearly bought one a very long time ago.
What part do you think I should look up? an abs bearing maybe?
 
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Brim987

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Ok I just went outside all fired up to unclip wiring pins and clean it all up but quickly ran away.
Please forgive my ignorance here..
As far as I can tell the abs pump and ecu are the same unit. I wanted to unclip as per the link earlier in this thread
but it's not the same. Obviously, I don't want to bend any pins. Do I need to disconnect the battery, do those 2 clips just push in somehow?
There's 2 other pics of, errr, lots of wires with plastic connectors on, any thoughts if they could be relevant?
I don't know what the silver box next to the battery is.
It's all a bit grubby in there, wouldn't suprise me at all if a there's a dirty/rusty pin somewhere but it's knowing what to try..

abs and ecu maybe.jpg
dunno 1.jpg
dunno2.jpg
 
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Brim987

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I just found a youtube vid where a guy unplugged the left front and piggybacked the live wire from the right wheel.
So the signals were identical, computer happy, mot passed. Then unclip it, let the computer turn the abs off as usual, all good.
I just can't get in there to try it, not that I would obviously.
 
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