need help with the ASC

[dt8068]

I picked up my e34 back in november and it runs great but I have been having a problem with the asc, after about 20 or so minutes of driving the asc light will come on. Up until then it works perfectly and i can turn it on and off using the switch. The time period the asc will work until the light comes on again gets shorter if it is warmer outside. (If its cold out the asc will work longer) The asc light has never come on during start up, only after driving a while. I searched through the forum and could'nt find anything on this issue, any ideas? help would be greatly appreciated. I posted a few weeks ago on the issue but no response.

By the way im fairly new to the forum and searchingthrough it has been a great help

[tim]

I can tell you with a fairly high degree of confidence that your abs module is failing. It's actually pretty common, not just on BMW's. The good news is that you can take yours off, have it reconditioned, and it will be fine. Or you can get a new one. Here's a link for I guy I can personally vouch for-http://www.modulemaster.com/. There are many others though that may be cheaper or more convenient. The deal is that you take it off (your brakes will work just fine- but you won't have ABS), send it off and when you get it back you just put it back on. Check the FAQ on module master's site. The problem with getting a new one is that it must be recalibrated ($dealer$).

For more details on symptoms, go to the roadfly e39 board and do a search on "1999 ABS Module Failure." The modules failed on practically that entire model year. There was a design issue that gradually caused the input stages to fail due to insufficient wire diameter for the amperage. It works until it heats up. It didn't help that the ABS module was sitting, unshielded, right next to the exhaust manifold.

I know you're thinking- but my problem is ASC, not ABS. Well, ASC is just an overlay program on your car's ABS.





I picked up my e34 back in november and it runs great but I have been having a problem with the asc, after about 20 or so minutes of driving the asc light will come on. Up until then it works perfectly and i can turn it on and off using the switch. The time period the asc will work until the light comes on again gets shorter if it is warmer outside. (If its cold out the asc will work longer) The asc light has never come on during start up, only after driving a while. I searched through the forum and could'nt find anything on this issue, any ideas? help would be greatly appreciated. I posted a few weeks ago on the issue but no response.

By the way im fairly new to the forum and searchingthrough it has been a great help

[dt8068]

thanks for the information and link, i will look into fixing it. I figured it would be failing but the ABS light apparently goes on along with asc when it goes (like you mentioned the asc is a function of the abs module)

[tim]

I bet you can get yours done cheaper than module master, but again, I only give advice where I have personal (positive) experience. Others on the board have had positive feedback for "BBA-Reman" (http://www.bba-reman.com/) as well. Dont send it to Chico's Bail Bonds and ABS Module Emporium or the like. You only have one chance to not **** it up. Gavin may give you a price break, since his quoted price of $300 is for the more advanced DSC system module. I don't know what BBA charges. Your's is first generation and much much simpler and robust. My guess is that he will will just resolder your board and replace the input stage wiring with higher quality silicone jacketed wiring. Simply remove the screws and release the multipin connector, and lift the black plastic module away from the metal hydro unit. Done!

Here's a visual:http://www.realoem.com/bmw/showparts.do?model=HE63&mospid=47410&btnr=34_0509&hg=34&fg=20

[[[**do not screw around with any of the other hard lines coming out the back of the metal cased unit** you are not doing any work on the hydraulic brake system at all, nor are you going to jack around with the asc vacuum line.]]]

I covered mine up with an anti static motherboard bag I had laying around, and taped it on, as well as putiing a baggie on the the connector to keep everything clean and dry.

When you put it back on after its fixed you won't need to clear codes or anything. it'll just work. Resist the temptation to open it up and do it yourself. I doubt many dealers have the expertise to recalibrate the older systems anymore- it's hard enough to get one who can do it on an e39- so getting a new one should be the absolute last resort.

[dt8068]

wow, thanks for the detailed information on removing the abs module. :) This helps alot! I checked the roadfly forums and it seems my problem is definitely the module failing, i didnt realize it was such a common problem (at least for the e39).

I'll eventually send it in to module master (much cheaper than dealer) but untill then i can live without asc
thanks for the recommendation!

[tim]

BTW, you can drive the car without the module on, you just won't have ABS. The standard mechanical hydraulic brakes will be unaffected.

[Scott C]

wow, thanks for the detailed information on removing the abs module. :) This helps alot! I checked the roadfly forums and it seems my problem is definitely the module failing, i didnt realize it was such a common problem (at least for the e39).

I'll eventually send it in to module master (much cheaper than dealer) but untill then i can live without asc
thanks for the recommendation!


I have to suggest that instead of spending $300 on a repair, you consider getting another "used" one? You may find something like the below unit for a lot less... Just make sure you get the "correct" one for your car. This one listed does not have traction control - just verify the numbers match with your existing one. "Some" of these sellers will assure you that these are not dead on arrival.

http://cgi.ebay.com/ebaymotors/BMW-abs-control-brain-530i-e34-530-anti-lock-brakes_W0QQcmdZViewItemQQcategoryZ33560QQitemZ8035 467602QQrdZ1QQsspagenameZWDVWQQtcZphoto

Scott

[tim]

I have to suggest that instead of spending $300 on a repair, you consider getting another "used" one? You may find something like the below unit for a lot less... Just make sure you get the "correct" one for your car. This one listed does not have traction control - just verify the numbers match with your existing one. "Some" of these sellers will assure you that these are not dead on arrival.

http://cgi.ebay.com/ebaymotors/BMW-abs-control-brain-530i-e34-530-anti-lock-brakes_W0QQcmdZViewItemQQcategoryZ33560QQitemZ8035 467602QQrdZ1QQsspagenameZWDVWQQtcZphoto

Scott

Scott- even if you get a different one from any source- new used or otherwise, it will have to be recalibrated. It doesn't matter if its the same part number. That's about a $600 job. Maybe $400 if you have a friend. It takes about 6 units of shop labor. That's why the market is so strong for the reman. ABS units. ECU's and EGS's are drop in replacements. Bosch ABS units need to be calibrated to each individual hydraulic unit. I agree that if you can get the right one for $89, and get it calibrated for less than $210, you'll come out ahead. I don't think the e34 units will be $300 either. The early pre-DSC bosch units are very simple- they only have six sensors, versus the 14 in the later units. That makes them similar to the GM and volvo units which typically are about $130-150 to rebuild.

[Scott C]

Scott- even if you get a different one from any source- new used or otherwise, it will have to be recalibrated. It doesn't matter if its the same part number. That's about a $600 job. Maybe $400 if you have a friend. It takes about 6 units of shop labor. That's why the market is so strong for the reman. ABS units. ECU's and EGS's are drop in replacements. Bosch ABS units need to be calibrated to each individual hydraulic unit. I agree that if you can get the right one for $89, and get it calibrated for less than $210, you'll come out ahead. I don't think the e34 units will be $300 either. The early pre-DSC bosch units are very simple- they only have six sensors, versus the 14 in the later units. That makes them similar to the GM and volvo units which typically are about $130-150 to rebuild.


Holy crap, did not realize they required all that labor. Blows my mind that they have to be customized/calibrated to a car. Thanks for the knowledge!!!

Scott