Thanks again both. As it happened the light went out today for all of 4 hours then when i started the car up again it was back on. I checked it again on the delphi and it was the phonic code again but no code for the sensor. I think its just a bad bearing now. Problem is i have no idea how to change it myself and all the garages nearby cant fit it in till week after next.

Not relay a DIY job especially if you say you're not to good with cars.
Stuff you would need: a lot of spanners, sockets, jack-stands, a wise... a bearing press/bearing puller.... possible to do with various size pipes...and screws..etc...

I don't recommend you do it.

Get on the internet, phone around... be prepared to dive 40-60 miles. You should find somebody who can do it in 1-2 days.

You can drive the car around. just be mindful you don't have ABS until it's fixed.

No ABS and no Electronic Braking Distribution, which is far more dangerous since the back wheels might lock any time during (hard) braking !!
Have a look here at what kind of job you'd face ...

https://www.fiatforum.com/cinquecento-seicento/288002-front-wheel-bearing-change-press.htm

Regards, Bernie

And here's the poor man's method ...

[ame]https://youtu.be/TwAkpEqY69c[/ame]

Regards, Bernie

Thanks, ive found a garage that will do this tomorrow for me. I got lucky with todays test, took light off with the delphi and it stayed off throughout the test, came back on during the drive home . Anyway, i'll let you know if this fixes the problem as soon as i know. I appreciate all the help. If this doesnt sort it then im stumped, 3 sensor cables, cleaned up the module and new bearings seem to cover the entire lot of things that could be wrong

To replace the bearing you dont need a press/bearing puller since the bearing is built into the hub cap you just replace the hub cap. 2 SKF WHEEL BEARING KIT cost about £93

Here is an inserting video that show what is probably wrong with your bearing reluctor ring.

Yes but the bearing cost £30 and labour for fitting it £50 so this way works out cheaper . Ive seen that link where Bernie linked it earlier and its a lot of work with tools i dont have, for eg i dont own a 32mm socket. This way is cheaper and less work for me and having it done by a mechanic should mean a better chance of it being done right

Agree ! If you don't feel confortable in doing something, don't ... But get informed about how things are so you won't get fooled by dishonest people (yes, there are some ;-)

Regards, Bernie

Well that tears it. Had it back from the garage and it was squeaking so i took it back, turned out to be the dust cover so he adjusted that then put it back together. Now the brakes are soft as hell, so much travel in them. He checked for leaks, none, bled them and some air coming from back o/s, redid all the fluid then checked again, more air. He thinks there is a small enough hole in the caliper to allow air in but no fluid out so i now need a new caliper.

To top it all off i just put the delphi on the car, i get 0031 front ns sensor - present and even when i wipe the codes and the light goes off it comes straight back on when i turn the car on again. Its a flaming nightmare, thats worse than when it went in and ive also got the addition now of brakes that are so bad ive got to cancel 5 lessons tomorrow and possibly the week long intensive course next week meaning i'll have to pay for the guy to take a retest. Never ever buying a fiat again but more than a little upset at whats happened so far.

basil1492

Don't buy the caliper, it's 99% not the cause of the soft brakes... can you describe the method they used to bleed the brakes?
I'm sure they didn't keep an eye on the fluid level.. and some air got in the brake/master cylinder..... maybe as far as the ABS unit.
Will be a lot harder to bleed... but not impossible.

When you used the block connector on the sensor to loom shouldn't matter... but might be worth reversing the wires)

This is why as said a few posts back to also check the resistance of the wires!

Are you sure Dephy is reading the correct wheel?
Try disconnecting the sensor and then read the codes.. a few times.. see if anything changes.

I watched him bleed the entire system. The liquid i had in there was green, its now yellow and completely changed. Did 5 whole tubs using the 1 way valve thing. As for the wires i know theyre right. Its white to yellow and black to yellow/black. Ive checked and its right way around.

PS when they changed the bearing they didnt even take the pipes off so it shouldnt have needed bleeding at all. As it happens when i took it there there was a little too much fluid in there and it was the same whn i got it back, just above max

Btw Aurick, thanks for the advice. If you can explain how the air would get in the system that would help me. To change the bearing he took off the caliper but didnt undo any of the brake lines. Im guessing that the only way air could get in is if there was a break in one of the seals, thats why i believed the guy when he mentioned the caliper leaking.

Could you also tell me how to bleed air from the master cylinder in case that is the problem please.

Best and easy way.. use a pressure brake bleeder.
http://www.ebay.co.uk/itm/Gunson-Ez...136120?hash=item3a9859f7b8:g:qHYAAOxyXDhScojU

It's a can/bottle with brake fluid.. that gets screw onto of the mater cylinder.
It gets connected to a pressure regulated air supply; a small amount of pressure is needed.. like ~0.3 bar.
Then the bleed nipples are unscrewed.. and the small pressure forces fluid through the pump, the abs unit, the lines, then the caliper.. and out.
If the pressure is to high the reservoir on the brake pump can jump off, or even crack.

Another system is the vacuum system

It just connects to the bleed nipple... loosen it .. and pull a little vacuum.. the fluid will be pulled through the system. No chance of cracking the fluid reservoir or having it jump off the pump.... but you can get false air in the line (air can sometimes let in the bleed nipple not from the caliper.. but through the threads of the nipple).

In some cases it it necessary to use the appropriate interface to start the ABS pump while bleeding to get some of the air from the pump (it's almost never the case.. but i did have to do it when i replaced my brake pump)

This systems are a lot safer that classic bleeding, because the in the brake pump there will always be a part of the cylinder that is never used in normal operation ( towards the bottom of the pump), that part will sometimes be not as smooth as the regularly used part.. and sometimes even have a bit of rust. When bleeding, pumping..pressing the piston through hat part of the cylinder, the seals on the pump's piston can get damaged ... leading to either air getting in the pump..leaks.. or even the pump slowly loosing pressure when brakes are applied.

I did have one brake pump fail this way (probably because of classical bleeding... when somebody pumps the brakes and somebody else loosens the bleeding nipple).... when I would press hard on the brake pedal it was ok; but when i pressed slowly gently the pedal would slowly go to the floor. In my case i did not have any air in the system.

Thats what mine is doing, going slowly to the floor i mean. Its funny because the brakes actually work, theres just a lot of travel in them.

Im happy to get an easy bleed system but my question is how did the air originally get in? You say the bleed screw thread for example but the brakes worked perfectly after he did the bearing but there was a squeak. I took it back, he took the caliper off whole, noticed the dust cover thing was touching so bent that back a little then replaced it. He never touched the bleed screw at that point or even when changing the bearing, no pipes were loosened, not even the cap from the abs fluid/

He thinks there may be a leak in the caliper but i find that hard to believe. My guess would be that when he lifted the caliper off the pipe gets bent back as the caliper is lifted over the disc, if i had to guess id say a small brake in that pipe is more likely than the caliper where it was kinked or something. The problem is its letting air in (when he bled them later the air comes out, you let it stand for a few minutes then bleeding again gets more air out) but no fluid leaks out so i can see the leak.

With all that info would you still say its just a bleeding problem?

After talking to a few mechanics etc there seems to be 3 possible problems to this. Firstly that the bearings are loose (unlikely as it was pressed in properly and looked fine, also wheel doesnt shake back and fore). 2nd that there may be air trapped (as Aurick said), apparently if its too hard to get out the normal way its suggest to do a reverse bleed meaning use a syringe, remove the fluid lid, loosen the bleed screw and inject fluid into the scre which then pushes all the air up into the open reservoir.

The last one which will be the most expensive is a reversed seal in the master cylinder. No way to fix this, just need to replace it so this is my last option. Apparently its very unlikely for it to happen and if it does the brakes are supposed not to work at all where mine do currently work but it just has a lot of travel. With mine if i pump them they get more solid but drive a few minutes and theres a lot of travel again.

The garage is going to double check the bearings tomorrow then try and bleed them again. To be honest i have little faith in this garage now as it was up to me to find these possible solutions. All they said was they were stumped and actually had me call a mechanic friend of mine as they had no idea what could be the problem.

The abs light has finally come off, just got to wait now and see if it comes back on or stays off this time.

Since you have butchered the wiring get a auto sparky to replace the wire between the abs sensor and the abs control unit....

My guess is high resistance somewhere between the abs modulator multiplug and the sensor


As for the green fluid I hazard a guess the service schedule has not been adhered to (2 yearly changes incl clutch)

The leaky rear slave is going to be another issue and require another cylinder or caliper

Thanks Andy but as i say that part may be sortd now. Even if it isnt that definitely isnt the problem with the spongy brakes, thats something else. If the abs light does come back on i will definitely get that part done by an electrician

Hi Basil,

no doubt here: spongy brakes getting harder when pumping IS air in the system. The only time after initial bleeding at factory that one need to bleed a system is when an intervention is done on it. If a complete flush is done (recommended every second year) properly it doesn't need bleeding either. By properly I mean performed by a pro, using pro's tooling and equipment, i.e pressurized brake fluid reservoir...

Air entering the system: almost impossible if you don't see brake fluid leak(s) ! The fluid in the system is compressed at pretty high pressure vs the little 1 bar of atmosphere. Even when releasing the pedal the fluid is pressurized by the brake springs (drums) or internal sealer ring (disk) to return to the reservoir.

When not activated, the ABS does nothing, it's just a pass-through device, no difficulty here to bleed with the standard method (at brakes bleeder), one doesn't need to losen ANY pipe on the ABS distributor nor on the master cylinder !

My flushing method:
- starting with (say) green fluid in the reservoir, empty it to the bottom and fill with red fluid (or recommended fluid if of a visible color difference.
- install the pressuring cap (I modified one from scrap with a tyre valve) and give it a 1/2 bar of compressed air
- clean the R-R bleeder, install the piping and the empty bottle on the bleeder, losen it untill you see the new fluid color arriving in the collecting bottle then shut the bleeder.
- do the same for RL, FR and FL bleeders.
- You will have to check the fluid level and pressurization time to time !!

Once done, start over with recommended oil if you did not use the right one (for color difference).

If you're brave you can also (instead) air-flush the system:
- remove fluid from reservoir
- install the cap and pressurize (1/2 bar)
- install piping and collecting can at RR wheel, open bleeder until air comes out, shut off bleeder.
- do the same on RL, FR, FL wheels
Once done, remove pressure, fill with fluid and start over until pure fluid (no bubles) is seen at piping connected to bleeder...

I found those methods better than the vacuum or one way valve one because with suction some air can come in by the losen bleeder, initiating a false positive air in circuit diagnostic.

Any car with poor maintenance or put in bad hands will soon or later show various problems so don't blame your GP for that. Even a Jaguar needs good care or will fail as well (BTW I've never seen a Jaguar in a back-street garage ;-)

GP's are equiped with BOSCH ABS (German technology) possibly a BOSCH ECU... FIAT is the inventor of common-rail injection engines (used woldwide) and his FPT factories provide engines and gearboxes to many car makers...

Regards, Bernie

Well, took it to another garage and it seems to be sorted, it needed another half turn of the hub nut which was loose enough to allow a bit of wobble. As for the abs light its been off 2 days now, fingers crossed it stays that way. Thanks to everyone for all their help, very much appreciated. Being a driving instructor means your car off the road equals no income.

Half a turn !? and suggesting the caliper got a leak !? not really a recommended address...
Is you car equipped with dual drivers pedal set ? That could be a potential source of air intake (maybe) ...

Regards, Bernie