ABS control unit repair

[cyclogenesis]

Just a post to say thank you to everyone who contributed to this thread. Took the ECU apart at the weekend. I could not see any breaks but I "re-soldered" the points marked and put the unit together again. It wasn't too pretty and I probably need to get a finer iron point but, the light is out and has not come back on. So.....I have either solved it....or fried the circuits that power the fault light! Anyway, I took it for a test drive and the brakes appear to pulse so fingers crossed.

Thanks again, this has saved me a lot of money/grief.

Just got to get that flaming rattle sorted now.

VOC membership renewal in the post!

[roy chu1]

Hi everyone,

I had a go at the ABS/ TRACS ECU today and got some help with the solidering, To get the case of was a little pain but managed it.

Anyway I had my MOT yesterday and it failed on a CV Boot and the ABS light, which was my biggest fear.

Anyway today I was kind of crapping my pants excuse my language, when I opened it, the joints looked fine, but I told my friend to go over the points as on the diagram, it did look very tidy, anyway it went back in the car.

The next thing was to see if it worked and if the light went out make sure it didn't come back on when I got to the MOT place.

Anyway the light has not come back on and I have another ear of MOT which is great, so I would recommend this fix, I was prepared to go straight to volvo for the scan and to buy some tracs abs sensors, as the light in the past kept coming on and off.

Anyway I shall see how long it will stay off, I will update this post.

So just to record,
The light first came on in 2005 at at 125k but was more frequent last year in 2006.
MY Volvo V70 T5 1998, 171k, ECU resolder done on 11th January 2007

Thanks to all for there advice and lets keep spreading the word as it does seem to work. I know Volvo are not going to do us any favours.

[Jod T5]

Originally Posted by lankybob

Jod, do you think this could be the problem with my ABS? (get a rubbing friction sound from the front left wheel until the TC light comes on (used to be 10mph but now sometimes until 20mph) and then stops. After that i don't get the problem again but obviously because the lights are on i don't have ABS or traction control

sorry gareth i missed this one...
what should happen is that when you start the car the t/c and abs light comes on and this should stay on while the ecu runs various checks on the system...i think different ecus work differently in that my teves system does its checks and turns the light out without the car moving but some people say the vehicle has to move before the light in extinguished...you would probably have to clarify this point with someone like chris rogers....
if the light comes on after the checking cycle i would expect you have a problem...
this grinding noise, is it when braking and only when the warning light is on...?
there is no grinding ever with the light off...
does the light ever come back on after you have gone past the 20mph stage, like when stopping at t/lights....
im thinking maybe the reluctor ring on the c/v joint....this can give a grinding noise under braking, it is a problem i am having with my o/s/f brakes at the moment
cheers
jod

[Neil.D]

Out of interest, how much is a new ABS moule fom Volvo??

[Jod T5]

Originally Posted by Neil.D

Out of interest, how much is a new ABS moule fom Volvo??

too much.....i would not expect too much change out of £450 by the time it was fitted....
cheers
jod

[lverona]

Just thought I'd reply quickly to this thread, as I have just carried out this repair and found the info here invaluable.

It took all day to come to the conclusion that it is impossible to buy an E5 female torx socket anywhere excluding the web. Eventually I used an E6 (which can be bought anywhere) and this sufficed (although was not as easy on the bolt heads as an E5 would have been).

With the use of a dremel, the case was apart in several easy minutes.

After a couple of failed soldering attempts, I realised there was a clear rubbery thin layer on the surface of the circuit board! I cut away where necessary and soldered the joints in as directed in the photographs provided earlier in the thread.

Silicone around the edges, pack of laminate floor on top of the unit for a few hours and then the unit was refitted in seconds.

The result? No ABS or TRACS light so far.

Time will tell, but I'm feeling positive.

Many thanks to all those that have posted about this repair and gave me the confidence to tackle it myself!

Thanks to all, I'm no expert by any means but this was easy and has worked a treat.
Just to add to previous points, a 4mm socket works to remove the ecu, a dremmel was invaluable in opening the case and i found myself too clumsy to re solder so just re melted the solder which was there already and it's worked!!
Watching the light go out at 20mph was superb!
Thanks again to all involved

[johnnyturbo2002]

Yes I have and it was fast and easy..and best yet, cheap!
Victor is extremely professional and I would recommend him very highly. He is also interested in other electrical problems that we volvo owners might have so if there are any extra parts with a reoccuring problem we should give him a shout andsee what he has to say. I'd say do it if you haven't done it already.

[britten_mark]

I'm tempted to try this after being lifted for 90 quid by an auto electrician to tell me all the wheel sensors were OK.

The only thing that worries me is cutting the case; some pics would be wonderful. Also if I do this and do not cure the light does that mean I can't then take advantage of the £100 reconn'ed units as they presumably want an undamaged exchange???

[Owen850]

People, I have an ABS unit from my 850 breaker left in the garage so if anyone makes a mess of their unit they can have mine for a rediculously cheap price covering postage!!

Here to help

Owen