posted by
someone claiming to be Mikebox
on
Mon Sep 12 05:22 CST 2005 [ RELATED]
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Ok, I now have the intermittent dreaded ABS/TRACS light and problems with the ABS pump engaging randomly. Has anyone used the guy in Calif that claims to rebuild the controller for about $150? I think there is a link on this site somewhere also but know that he advertises on ebay.
I assume it is a deteriorated solder joint on a circuit board as it does seem to be better when hot.
Has anyone seperated the controller module halves and attempted to locate and repair the joint themselves?
thanks,
Mike
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posted by
someone claiming to be kcarl
on
Wed Sep 14 01:06 CST 2005 [ RELATED]
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I attempted to repair my abs module. Here is what I found:
Opening the case was a real pain. First, I removed the 4 clinch rings from the posts. Then I worked an exacto knife and dental tool around the sealant for quite a while. Cover and base are joined by a tongue and groove configuration. This, combined with the sealant, makes it very difficult to remove the cover. I was not able to open it without buggering up the joints. If you could find a chemical to soften the mastic, it would be a tremendous help. Finding a tool to get past the "tongue" would be great too. The repair centers might use a dremel tool, but i was afraid to without knowing what I was cutting into.
After finally getting inside the module, I found the PCB coated with a thick, clear, viscous gel. I used a microscope to thoroughly inspect solder joints and appearance of components. No visual defects were noted, so I proceeded to reflow all the connector pins and anything resembling a cold solder joint. I resealed and installed the module and had no problems for about a month. Then, the same problems resurfaced. At this time, I decided to send the unit to www.autoecu.com. I chose them simply because we were on the same coast and thought it would be faster. It took longer than I expected to get it back due to shipping and timing, but the unit has been working fine for several months.
If the defect was related to a cold solder joint or broken PCB run, I couldn't find it, and I was using a very nice lab grade microscope designed specifically for PCB inspection. The PCB runs looked new, as did the solder joints. Maybe I should have added solder to the pins, but I know what a good solder fillet looks like, and these looked fine. I suspect the guys that repair these successfully know exactly what is wrong prior to opening the unit, and of course, have experience with the unit. I'd love to know exactly what was wrong with mine and maybe it was just an oversight on my part. I'm not trying to discourage anyone from working on the unit but want you to know it's a real pain, and you could easily ruin the unit. Sometimes you just have to pay for knowledge and experience.
Good luck and thanks to those who have helped me with my '98 V70 problems in the past. It can be a real challenge at times - a very love / hate relationship.
kcarl
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posted by
someone claiming to be Mikebox
on
Wed Sep 14 02:00 CST 2005 [ RELATED]
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Thanks for the firsthand account. I thought i'd use a dremel but sort of hate to cut the tongue out of the joint.
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posted by
someone claiming to be kcarl
on
Thu Sep 15 00:28 CST 2005 [ RELATED]
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Mikebox,
Even though I had worked on mine and buggered up the tongue joint, the company I listed above was willing to repair it. Maybe start with a reasonable attempt without the dremel and see how it goes? Keep in mind that the mastic is on both sides of the tongue joint, so you can't get to all of it for removal. Also, I think there are a couple of small areas where the tongue is short, so you can get through to pry the cover. If you do mess up the joint, the cover can be held in place with the 4 posts and clinch rings, while the gap is filled with mastic or a non-acidic sealant.
kcarl
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posted by
someone claiming to be steve@cbe
on
Fri Sep 16 22:58 CST 2005 [ RELATED]
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trust me it wont work, i have tried to pry them apart and to slit the sealant etc.. it just doesn't work. a thin cut off wheel is the best way and you can control the penetration depth to prevent internal damage to th pcb. a long as its sealed again with sealant there is no problem as the metal posts hold it together.
steve.
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posted by
someone claiming to be steve@cbe
on
Mon Sep 12 21:25 CST 2005 [ RELATED]
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hi,
in answer to your questions i work for volvo as a tech and as such have come upon this problem many times. the problem is not a problem with the module as such but its exactly as you said in that solder joints on the circuit board do fatigue where the plug socket is soldered to the board and then the module detects intermittant open circuits and this makes the light come on. sometimes the module itself does fail and cant be repaired but this situation is pretty rare, 90% of the time its due to bad solder joints and when you send these away to be repaired all they are doing is resoldering the board which is not that hard to do for someone with experience with soldering.
a tech can tell if its bad solder joints because 9 times out of ten the light coming on will mean there are certain fault codes in the module (due to open circuits) these are normally right rear wheel speed sensor,other wheel speed sensors and sometimes pump motor faults.
anyway hope this answers your post, any questions just ask me..
steve.
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posted by
someone claiming to be Mikebox
on
Tue Sep 13 02:05 CST 2005 [ RELATED]
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Thanks, Steve.
I haven't tried to open the case up; do you know what it is sealed with and what might be the best method for opening without "buggering" it up? I have repaired a number of circuit boards on GM, Mazda, Ford products in the past and certianly think it is worth a go with this. Are the control module faults read wtih Vadis at the dealer or some other diagnositcs?
M
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posted by
someone claiming to be steve@cbe
on
Tue Sep 13 21:11 CST 2005 [ RELATED]
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ok, to open the best way is to use a tool like a dremel with a small diameter thin cut off wheel and cut the "seam" around the module with the tool making sure to not go into the module any deeper than about 5-6mm this way you wont contact the insides. you need to re-solder the pins for the big multiplug and the two pins for the pump motor plug. some of these wires are small so you need to take care. when you reassemble it use black RTV silicone or simaler so its waterproof.
as for the diagnosis it depends on if its a old or new shape v70, the older type uses volvos VST the newer v70 uses vadis/vida. a aftermarket scan tool may work although i have not used these. good luck, not many people know about this although a lot have had this problem and are charged a lot of money for what is a fairly basic re-soldering job.
steve.
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posted by
someone claiming to be Mikebox
on
Wed Sep 14 02:01 CST 2005 [ RELATED]
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Thanks again, Steve. I may give it a go later this week. If successful, I will certainly post what was found and repaired.
Thanks,
M
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posted by
someone claiming to be steve@cbe
on
Wed Sep 14 21:10 CST 2005 [ RELATED]
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sorry but after reading that other guys post i realised i missed explaining a couple of points. yeah you need to get the clinch rings off the metal posts first they can be reused later. and as for that clear gel just scrape it off the area off the socket pins carefully before you do any soldering.
also check carefully the two wires that go from the pump motor to the circuit board as the insulation tends to crack and flake off these wires in hot climates then they touch and can cause the abs fuse to pop.
steve.
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Interesting post . . . my ABS controller went out on my 98 V70 around 50,000 and is still out at 114,000. I pulled the controller off once and it appeared to be "hermetically sealed", but other posts led me to believe it was faulty solder joints.
It might come apart easier when it's hot. The engine compartment itself has to be good for at least 300 degrees F. Perhaps using an oven will work.
My speedometer/odometer/cruise control has mostly been non functioning the past 3 weeks and after looking at the alldata sheets, it seems to get it's speed signal via the ABS unit. What puzzles me is that the spedo/odo/cc has all worked fine even though the abs unit failed years ago. Since I'm sure many pins are located on the connector to the abs module, it can fail at a later date or perhaps not, just depends.
I'll be taking another crack at it. I've gotten along fine without ABS but getting along without a spedo/odo and cruise control is nuts.
As an aside, when I retrofitted the Dynaudio/Alpine sound system into my car, the Dolby Pro-logic module was faulty. I pulled the lids off & examined the circuit board and found close to 30 or 40 poorly soldered joints. Some without any solder whatsoever. After retouching these and reinstalling, it's been fine since.
Regards,
Mark
--
1998 V70 T5 110Kmi; Previous car: 1985 SAAB 900T, 254kmi
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