ABS shenanigans

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
I've been tackling on and off an ABS fault with the Z3. At times I've simply found more important things to do like the sills and a recent airbag fault which is now rectified. At times it just annoys me and I go and paint the fence or something.
I'll start where most things start. It began with an intermittent fault. Normally I'd depress the brake pedal, the abs could be heard engaging rumbling and the horrific ABS light of death would illuminate. Then next time I went for a spin, all would be well and it would go out.
At some point in which I can't recall the ABS light stayed on and won't go out. Now sometimes my cheap OBD scanner will read P0500 (speed sensor A) and sometimes it won't. I've also tried a Foxwell scanner, Delphi scanner and the 'Launch' scanner which is a £700 all singing all dancing system so I'm told. Again speed sensor A. Now I've replaced all wheel sensors (or effectively used the same new sensor and gone round each corner to eliminate each sensor). Still no change. Again sometimes the diagnostic scanner will read it, but very rarely. I've unplugged the diff sensor and ran it. I have no Speedo as would expect but the scanner doesn't detect it's been removed. I've also unplugged a wheel sensor and again although showing an ABS fault on the dash nothing detected on the scanner. I've removed the module from the ABS pump. Checked connected visually on the plug and on the large terminals. Cleaned up and refitted. No change. Fuses are good. I feel I need to delve into this more electrically so I've checked for continuity on the diff sensor and tried feebly to check the wheel sensors for continuity. Now I am aware it could be the reluctor rings but is this more likely to be the module? Is there anything from my description to dictate that perhaps I should remove the module and pump to be sent away for repair or source a secondhand unit?
 

colb

Zorg Guru (V)
British Zeds
Joined
Nov 25, 2012
Points
178
Location
Newport, South Wales,UK
Model of Z
Z3 M43 1.8 (1999) and Z4 E85 2.0i (2007)
I reckon you have done all you can to resolve this, best option would be to send the unit away for repair, I suspect that the intermittent nature you are experiencing is probably down to dry joints inside the unit.
 

137699

Zorg Guru (I)
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Jan 30, 2020
Points
89
Location
Hampshire
Model of Z
M Coupe 3.2 S50
Relcutor rings would be my guess... Have you visually inspected them?
 

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
Out of interest do the complete:
If I change the abs pump with module complete do I need it pairing/coding with the car or plug and play?
If I changed just the module does that need coding with the car or plug and play?
 

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
Out of interest do the complete:
If I change the abs pump with module complete do I need it pairing/coding with the car or plug and play?
If I changed just the module does that need coding with the car or plug and play?
I've actually answered my own question and found some useful stuff on the forum. I'll attach for anybody else interested.
 

Attachments

Stevo7682

Zorg Expert (I)
Supporter
The M44 Massive
Scottish Zeds
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Apr 1, 2016
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Location
Maybole , South Ayrshire
Model of Z
Z3 Individual Dakar / Orinoco Individual
In answer to your other question.
If you change the module yes it will need coded.
The Abs side will work correctly its the traction control side of things that need coded
The traction control switch will work OK light will go on and off when you press it but the traction will be permanently disconnected unless you code the replacement module.
Stephen.
 

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
In answer to your other question.
If you change the module yes it will need coded.
The Abs side will work correctly its the traction control side of things that need coded
The traction control switch will work OK light will go on and off when you press it but the traction will be permanently disconnected unless you code the replacement module.
Stephen.
Thanks, top man.
Looks like I'll need to buy INPA then
 

Stevo7682

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The M44 Massive
Scottish Zeds
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Location
Maybole , South Ayrshire
Model of Z
Z3 Individual Dakar / Orinoco Individual
What i should have also added is the hydraulic side of the pump will only need bled to replace.
If you suspect that it is the module at fault as in your download above ( don't know about the earlier pumps) the later ones you can take out the 4 inverted torque bolts and multi plug and remove the module without splitting the hydraulics .
The car will drive with the module removed but obviously will have no abs or traction control and lights will come on dash but the brakes will work same as for a non abs equipped car.
 

Bampz

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British Zeds
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Aug 2, 2016
Points
94
Location
Pembrokeshire
Model of Z
2.8
Reading with interest , I would be inclined to check relcutor rings first before doing the module , and does the same wheel sensor fit both front and rear wheels as I thought they were two different sensors?
 

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
What i should have also added is the hydraulic side of the pump will only need bled to replace.
If you suspect that it is the module at fault as in your download above ( don't know about the earlier pumps) the later ones you can take out the 4 inverted torque bolts and multi plug and remove the module without splitting the hydraulics .
The car will drive with the module removed but obviously will have no abs or traction control and lights will come on dash but the brakes will work same as for a non abs equipped car.
Thanks. I have the facelift and have already split the module from the pump to clean and inspect.
I'm gonna go ahead and remove the module and remove the casing to check for any damaged internals.
 

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
Reading with interest , I would be inclined to check relcutor rings first before doing the module , and does the same wheel sensor fit both front and rear wheels as I thought they were two different sensors?
Yes they are different have changed front and rear respectively. Rings look fine.
 

Stevo7682

Zorg Expert (I)
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The M44 Massive
Scottish Zeds
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Maybole , South Ayrshire
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Z3 Individual Dakar / Orinoco Individual
You need to cut the casing open as its a sealed unit.
I had to do it to my Dakar ( been fine since repair) you need to cut it open just above the central line ( be careful doing this) and then bond back together when finished )
15937116921641412379501715148046.jpg
 

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
What ABS unit do you have - the DSC one? the ASC one?
ASC

So I've split the casing. Slightly dubious positions of the Stanley knife and the unpleasant sound of snapping plastic.
Indications suggest it's not the first time it's been opened or do they all come with random lettering?
 

Attachments

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
So an update. Module arrived and success...sort of. The car now communicates properly with diagnostics. Reporting that all speed signals had an error. A quick reset and down to the rear left sensor. Now previously I put a fairly cheap 'Stark' (not Iron Man) sensor in there and swapped the left for the right and put the right on the shelf for the time being.
I have received two error codes for the sensor. I was suspicious of this so I swapped that for the one from the shelf (which was previously in the right). Another go and down to one error code still on the left. Next I swapped the two rears around. And hey presto the right rear is now at fault. So it seems that a) the module failed to communicate with diagnostics b) the OEM sensor was no good and c)it was the rear right all along. Phew!
 

brozier

Regular Member
Joined
May 6, 2017
Points
20
Location
NW Leicestershire
Model of Z
2.2i
I've actually answered my own question and found some useful stuff on the forum. I'll attach for anybody else interested.
Thanks for your PDF file. I followed it and repaired my Z3 :) Had to use INPA to clear the fault codes. The issue was the two connections to the pump, both were dry joints. I resoldered all the connector pins to be on the safe side.

I would add that be very carefull when removing the lid of the ABS ECU as there are components close to the edge of the board. Luckily Farnell do Automotive spec capacitors!
 

Christ87

Zorg Addict
British Zeds
Joined
Jun 17, 2019
Points
58
Location
Belton, North Lincolnshire
Model of Z
Z3 2.0
Thanks for your PDF file. I followed it and repaired my Z3 :) Had to use INPA to clear the fault codes. The issue was the two connections to the pump, both were dry joints. I resoldered all the connector pins to be on the safe side.

I would add that be very carefull when removing the lid of the ABS ECU as there are components close to the edge of the board. Luckily Farnell do Automotive spec capacitors!
Well you went one better than me by soldering it yourself. I bought a second hand unit and replaced it.

Update as of today. Right rear sensor replaced. All faults removed.
 
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