A8 Parts Forum  

Go Back   A8 Parts Forum > A8 D2 > D2 - Axles, Brakes, Suspension and Steering

D2 - Axles, Brakes, Suspension and Steering Brakes, Springs, shocks, steering racks, steering columns, suspension arms, wheel hubs etc.

Reply
 
Thread Tools Display Modes
  #1  
Old 23rd February 2019, 11:33 AM
Nognar Nognar is offline
Senior Member
 
Join Date: Jul 2017
Posts: 109
Default D2 S8 20" Wheel ABS Sensor Repair

Yes, I said repair which is a little odd but allow me to give some details.

My D2 S8 has the 20" wheels and that has a special ABS sensor that is not the standard unit as many of you will know. A normal A8 ABS sensor can be bought for about 10, the 20" Wheel version for the S8 is 170 from TPS/ Dealers/ eBay and even second hand is expensive.

So what to do

4D0927803E is the part number and I did not want to spend all that money and second hand is not worth it in my mind on a sensor. Hence I went on the hunt for something I could use from another VAG model that would work.

It took some time but I spent a whole 9 on one of these from eBay:

https://www.ebay.co.uk/itm/ABS-WHEEL...53.m2749.l2649

Its a B6 A4 unit part number 8E0927803A, it looked the same sensor from the picture so I though why not just give it a try.

The photo below shows the original S8 one on the right and the new A4 one on the left.



Yep, looks and fits perfectly. Sensor itself has the same dimensions, the only difference is the mounting plate is a little deeper so you need a longer bolt to hold it in.

Now the wiring harness is NOT THE SAME, therefore you need to cut the ABS sensor off it, do the same with the original S8 harness and solder the new sensor on and put some heat shrink on it. Hence why I called this a repair as you do need to cut/ strip/ solder to make up the old harness with the new sensor.

The result, works perfectly and looking at the measuring blocks on VAGCOM the readings are all good also.

161 saved
__________________
2002 Audi D2 S8 - Ming Blue Pearl
2003 Audi D2 A8 QS - Light Silver Metallic
2004 Audi A2 FSI - Akoya Silver Metallic


Last edited by Nognar; 23rd February 2019 at 11:47 AM.
Reply With Quote
  #2  
Old 23rd February 2019, 11:38 AM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Location: Devon
Posts: 2,525
Default

Great find

I've been looking (not very hard) for an alternative sensor for these - so far tried just the TT and D3 which aren't quite right. I will have to acquire a B6 one and give that a go
__________________


facebook.com/D2Doctor
Reply With Quote
  #3  
Old 23rd February 2019, 08:53 PM
Markiii Markiii is offline
Member
 
Join Date: Oct 2018
Posts: 97
Default

Interesting. 2 questions.

What was the problem you were fixing?

Why is the 20" wheel one difference?
Reply With Quote
  #4  
Old 23rd February 2019, 09:33 PM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Location: Devon
Posts: 2,525
Default

D2s which had factory 20" wheels have steel struts with larger wheel bearings whereas the non-20" FL cars have alloy struts. The ABS sensor for the steel strut is unique and genuine only so heinously expensive.
__________________


facebook.com/D2Doctor
Reply With Quote
  #5  
Old 24th February 2019, 08:45 AM
Markiii Markiii is offline
Member
 
Join Date: Oct 2018
Posts: 97
Default

By strut do you mean hub?
Reply With Quote
  #6  
Old 24th February 2019, 09:10 AM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Location: Devon
Posts: 2,525
Default

If you like yes. I call the bit that the control arms bolt to the strut or upright, and the turny bit the hub, but they are generally interchangeable Technically upright is probably more correct since its double wishbone rather than macpherson strut.
__________________


facebook.com/D2Doctor
Reply With Quote
  #7  
Old 24th February 2019, 09:12 AM
Nognar Nognar is offline
Senior Member
 
Join Date: Jul 2017
Posts: 109
Default

It was being replaced as it had failed, thrown a code and was no longer sending a speed reading.
__________________
2002 Audi D2 S8 - Ming Blue Pearl
2003 Audi D2 A8 QS - Light Silver Metallic
2004 Audi A2 FSI - Akoya Silver Metallic

Reply With Quote
  #8  
Old 24th February 2019, 10:06 AM
Markiii Markiii is offline
Member
 
Join Date: Oct 2018
Posts: 97
Default

Quote:
Originally Posted by MikkiJayne View Post
If you like yes. I call the bit that the control arms bolt to the strut or upright, and the turny bit the hub, but they are generally interchangeable Technically upright is probably more correct since its double wishbone rather than macpherson strut.
Yes upright, that's what I meant. We got there eventually

Must check what mine are
Reply With Quote
  #9  
Old 24th February 2019, 02:11 PM
HPsauce HPsauce is offline
Senior Member
 
Join Date: Sep 2011
Location: About 250m from HS2!
Posts: 6,895
Default

Quote:
Originally Posted by MikkiJayne View Post
D2s which had factory 20" wheels have steel struts with larger wheel bearings whereas the non-20" FL cars have alloy struts.
So there's obviously a reason for this, but what is it and what are the downsides of fitting FE 20" wheels to a car with non-FE alloy suspension?

Or were they just using up the stock of some suspension variant made maybe for the armoured vehicle or some other rare special option?
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!)
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
Reply With Quote
  #10  
Old 24th February 2019, 02:57 PM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Location: Devon
Posts: 2,525
Default

I honestly don't know. It is totally counter-productive to handling and ride comfort to fit heavy 20" wheels and then to couple them with even heavier steel uprights which weigh 5Kg more each than the alloy ones. They were specially produced for the 20" cars rather than something which needed using up and are available in both Brembo and HP2 brake fitment.

I can only surmise that something in the load calculations suggested that the alloy upright would not take the stresses of the 20" wheel (or for that matter the 3.3 V8 TDI) and so they designed new uprights from steel instead, and put the larger 92mm bearing in them.

The lower arms are also different for the steel struts - the lower rear has a different inner bush. Possibly stronger?

People have been running 20" wheels with alloy uprights for many years and they are absolutely fine. Whatever calculation it was, there is clearly a substantial safety margin in the alloy stuff. Its probably an extreme use case which no one will ever actually encounter.
__________________


facebook.com/D2Doctor
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 11:52 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.