Volkswagen Passat (1988 - 1997) - 1996 1.9TDi ABS ECU

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Sat 20 Dec 2008 18:43
1996 1.9TDi ABS ECU - tujags
Has anybody experience of removing the ABS ECU from the hydraulic unit? Haynes as usual says dealer job as Hydraulic unit has to be removed & fluid must not be lost from it. what a great design the earlier model ECU was under the passenger seat easy to remove etc - progress?????????
VW seem to have carefully designed this version of the Passat to make even simple service jobs awkward & inaccessible.
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Sat 20 Dec 2008 18:53
1996 1.9TDi ABS ECU - elekie&a/c doctor
Is this car fitted with Bosch or Teves abs sysytem?For what reason does the Abs Ecu need to be removed?
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Sat 20 Dec 2008 19:10
1996 1.9TDi ABS ECU - tujags
It is the Teves 20G getting rear sensor fault codes but sensors & 'cages' are good get ac output from sensors when spinning wheels. Have read that a faulty ECU can show these fault codes. was going to remove ECU & get it tested/repaired (£25 test or £100 repair with 2 year guarantee)

Edited by Dynamic Dave on 20/12/2008 at 21:00

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Sat 20 Dec 2008 19:19
1996 1.9TDi ABS ECU - elekie&a/c doctor
The abs unit can be separated from the hydraulics without any major problems.There is no need to dismantle the fluid system.the unit is usually attached by 4 or 6 torx head screws.The fault you describe is commonly a problem with poor solder joints on the abs pcb.hth
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Sat 20 Dec 2008 19:34
1996 1.9TDi ABS ECU - tujags
Thanks for the info I'm always wary of Haynes advice these days. I had a look at the unit it looks awkward some of the hydraulic pipes pass under the ECU about 20mm clear. I could probably 'ease' them out of the way a bit. I'll have another look & have a go at removal - mirror or standing on head job?
Poor solder joints sounds a likely cause I used to build radios etc but the old eyesight is not so good these days might be worth a look before sending it for repair.

snipquote - sorry but it annoys the hell out of me people who quote the message they're replying to after they've written their reply

Edited by Dynamic Dave on 20/12/2008 at 21:01

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Sat 20 Dec 2008 19:59
1996 1.9TDi ABS ECU - elekie&a/c doctor
I'm afraid you will not see much with the unit removed;the ecu is in a sealed plastic housing that needs to be carefully cut open to reveal the pcb.hth
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Sat 20 Dec 2008 20:14
1996 1.9TDi ABS ECU - tujags
Ah OK maybe I'll leave it to the experts! as they offer a 2 year guarantee against VW's £1000 price & 6 months guarantee.
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Sun 21 Dec 2008 10:40
1996 1.9TDi ABS ECU - PeterRed
I had some ABS problems with my 2000 B5 Passat. See thread :

www.honestjohn.co.uk/forum/post/index.htm?t=66455&...f

Not sure if the Teves setup is similar but it's probably worth taking a look at the BBA-Reman web site. My Bosch unit has been fine since.
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Mon 22 Dec 2008 22:55
1996 1.9TDi ABS ECU - tujags
Yes I know this company they have a good reputation, I am replacing one rear sensor that seems a bit soso awaiting postal delivery - Christmas! no the best time will test again if still faults will send unit to them for check or repair much cheaper than VW price!
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Mon 22 Dec 2008 23:26
1996 1.9TDi ABS ECU - VR6
I had the same issue with my 1997 Golf VR6. Kept showing rear ABS sensor fault. My mech said easy way to check if its the ABS ECU is to swap the abs cables over from the rear left wheel to rear right and then re-check fault codes.- in my car they are situated somewhere under rear seat which gives easy access. Not sure about your car.

In the end we didnt bother with this swap over, but 'tweaked' the pipes out of the way and removed the ECU, and soldered a few cracked joints. Cost me an hours labour, and a year later its still ok. No need to remove the hydaulic part or mess about with the braking system.

Depending on where you are my mechanic is Stealth Racing in Southam, Warwickshire. VW independant - they really know their stuff.
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Thu 25 Dec 2008 17:05
1996 1.9TDi ABS ECU - tujags
I'm certain one rear sensor was duff read open circuit even on a 20Mohm meter & no AC output when spinning the wheel. I have replaced it & got an AC output on a mV meter, should I clear the fault codes or just see if the fault light goes out. car is on SORN at the moment so can't move it very far. I was getting fault codes from both rear sensors. With Christmas etc I haven't had time to recheck the faults. The code reader is an Autel Vagscanner VAG305.
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Tue 27 Jan 2009 19:18
1996 1.9TDi ABS ECU - tujags
Update:
I had the ECU checked & repaired by BB-reman & refitted it still got one rear sensor fault the new sensor shows as OK now. Will try the swap over trick when I can.
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Sun 22 Feb 2009 18:35
1996 1.9TDi ABS ECU - tujags
update I changed the other rear wheel sensor & the abs warning lamp is behaving itself now.
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Fri 6 Aug 2010 22:21
1996 1.9TDi ABS ECU - probert993

hi there found this thread you posted a while back, i have a golf vr6 i have put my abs problem down to ecu under pump now, you mention soldering etc, when you take off the ecu from the pump how do you get in to solder etc does ecu split open or is board visible once its off, if you could help that would be great thanks

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