General Hopefully the final ABS/ ASR thread. Wiring Diagram and advice needed.

[john55]

I have a Stilo Multiwaon with the usual ABS ASR error coming up all the time.
I have read many posts on here about fixing it. Replacing the battery, even modifying the wiring so the ECU thinks the air-con is on. None of these address the real problem and only fix it temporarily. As cars dont usually have this problem from new and it develops over time and is worse when cold/ damp, I beleive there are 3 possible causes, or probably more likely a combination of the three.
1. Corosion or poor connection somewhere in the wiring
2. Bad layout of the wiring loom in the car
3. A fault with the ABS pump itself

As an electronics engineer, with quite a lot of experience working on cars (my latest was an Audi A8, where I saved the owner over £4K compared with what Audi would have charged to fix it. There are 49 computers and many Km of wiring in that car, but I managed to fix it and even educate an audi technician on how to fault find quickly on them).
Although I am new to Stilo's, I am learning fast (as things fail on my car) and I intend to systematically go through the ABS system and see if I cant solve this once and for all.

What I need is help from you guys, in the form of, wiring diagrams/ pinout for the ABS pump/ system/ ignition wiring in the cars.
Also has anyone else had a serious go at fixing this, and have found things which work/ dont work.
I want to start this weekend, so please post soon.
Thanks.

 

[Deckchair5]

Hi John
Does the warning come up immediately on start up and stay on?
Or does it only come on when you start to move the car?
Did you do any relevant work to wheels/ brakes/ suspension immediately prior?

I'll send some wiring diags if you need them but you may not need them as
the cure might be easy once we tie down the warnings

OK here you go

 

[john55]

I bought a stilo CD from e-bay, but it seems useless. Just a flow char kind of program stating basic faults and replace this/ that part.

The car has been sitting for over a year, and not driven. It has an ABS / ASR failure when the key is switched on, but afer that, it stops saying ABS failure, but the light remains on. It did go off for about a 10 mile journey, (ASR fail stayed on) but then came back on.
I have seen the car with both ABS and ASR lights off for a short period of time.
I have cleaned D4 (was clean) connector and ABS pump connector (which had some corrosion)
I have bought a new 096 battery which I will fit this evening. I am now thinking wheel sensor connectors.

I want to try to get it through an MOT tomorrow so will be spending most of tonight working on it.

My ABS fail is different to the common intermittent does it on a cold morning sometimes faults that are often reported.
I want to fix my obvious ABS fail and then go onto the intermittent one.

Please post circuit diagrams, or I can PM you my e-mail address if they are big files.
Thanks.

 

[john55]

Is it possible to have the diagram in a better resolution, to read the wire colours? Also is there a key to go with it.
Thanks.

 

[Deckchair5]

I'd go for the abs wheel sensors connectors, often just disconnecting and reconnecting the connectors gives the contact but I'd clean them up with contact cleaner.

You can check for voltage supply at the sensors and should get speed dependent square wave on return line when you spin the wheel

It'll be to big to post up fue to forum image size limitations but here's a close up of the business end

Key to the components is in the description

N= BLACK
B= WHITE
C= ORANGE
M= BROWN
A= LIGHT BLUE
S= PINK
V= GREEN
R= RED
Z= PURPLE
G= YELLOW
H= GREY
L= BLUE