Wiring Harness / Body Control (BC1) Failure
#1
10-13-2009, 03:49 PM
Wiring Harness / Body Control (BC1) Failure
Hey guys
I have an '02 Cooper S that died on me last winter. Preceeding this, I had all kinds of electrical trouble, everything from the alternator / battery not working properly through power windows, heater, headlights, interior lights, guages, temp sensor, and power steering pump behaving very erratically. As you can imagine, it's been a frustrating experience. So anyway, about february, my car died at work and after attempting to jump and trickle charge the battery, I had it towed to a Mini dealer and went ahead and bought a Cherokee which turned out to be extremely reliable and trouble free ('nother story). the dealer told me that water had gotten in through a bum seal on the sunroof and soaked the floor which shorted the wiring harness and to fix it would be about $4000 worth of labor - ouch! So I had it towed home and have been crawling through the labrynthine wiring harnesss with my trusty Fluke 87.
I haven't been able to find any really obvious flaws in the harness, yeah it's wet, but the insulation integrity seems to be there. However, all these faults seem to have a common link to the body control module BC1. It seems that Minis from that era have problems with the connectors leaking and shorting the board. So my question is, anyone else experience this? Is the BC1 compatible between vehicles? Can I grab one out of a junkyark '03, have the dealer program it, and stick it in my '02? Do I need to spend $460 and get one from the dealer? Your thoughts and experiences are much appreciated - thanks!!
I have an '02 Cooper S that died on me last winter. Preceeding this, I had all kinds of electrical trouble, everything from the alternator / battery not working properly through power windows, heater, headlights, interior lights, guages, temp sensor, and power steering pump behaving very erratically. As you can imagine, it's been a frustrating experience. So anyway, about february, my car died at work and after attempting to jump and trickle charge the battery, I had it towed to a Mini dealer and went ahead and bought a Cherokee which turned out to be extremely reliable and trouble free ('nother story). the dealer told me that water had gotten in through a bum seal on the sunroof and soaked the floor which shorted the wiring harness and to fix it would be about $4000 worth of labor - ouch! So I had it towed home and have been crawling through the labrynthine wiring harnesss with my trusty Fluke 87.
I haven't been able to find any really obvious flaws in the harness, yeah it's wet, but the insulation integrity seems to be there. However, all these faults seem to have a common link to the body control module BC1. It seems that Minis from that era have problems with the connectors leaking and shorting the board. So my question is, anyone else experience this? Is the BC1 compatible between vehicles? Can I grab one out of a junkyark '03, have the dealer program it, and stick it in my '02? Do I need to spend $460 and get one from the dealer? Your thoughts and experiences are much appreciated - thanks!!
#2
10-13-2009, 07:42 PM
I'm not sure on the 03 being compatible , use the dealers, call and ask parts for the part # for yours then the "junkyard" one and see if they match ...
Plan on around 2 hours labor for "reprograming" and a tow bill to get it there ...
Also check the connectors on the harness , as there can be water damage(very common on the power steering connector)
Plan on around 2 hours labor for "reprograming" and a tow bill to get it there ...
Also check the connectors on the harness , as there can be water damage(very common on the power steering connector)
#3
10-14-2009, 02:44 PM
Hey Venge, thanks for the advice! I found an ECU where the last 8 digits match, plus it came out of an '02 Cooper S with a 6 speed, so hopefully that's the good stuff. The guy at the Mini parts counter seemed to think that I wouldn't need to have it reprogrammed. We'll see. If it doesn't work, I'm out $115 and then I need to spend $500 or so getting a new one and getting it programmed. If it works, sweet! I get my car back for 115!
Is there anything you guys have done to seal up the connectors or the ECU itself? Usually on more high dollar ECUs everything's potted in epoxy whereas on this one any idiot with a fingernail can pry the case apart and see all the chips. Also what about sealing up the connectors a little better. Maybe rub vaccuum grease over everything?
By the way, I found that ECU off www.car-parts.com which I've had great luck finding good junkyard parts for other projects on.
Is there anything you guys have done to seal up the connectors or the ECU itself? Usually on more high dollar ECUs everything's potted in epoxy whereas on this one any idiot with a fingernail can pry the case apart and see all the chips. Also what about sealing up the connectors a little better. Maybe rub vaccuum grease over everything?
By the way, I found that ECU off www.car-parts.com which I've had great luck finding good junkyard parts for other projects on.
#5
10-15-2009, 07:28 PM
I am having the same kind of problems. Differences are even though its a 2002 Cooper S, I don't have a sunroof. So maybe water is coming from elsewhere? Where is BC1 located. On my way home tonight I had every warning light come on intermittently before the car died. When I got home and put it in the garage you could hear a relay clicking on/off somewhere under the hood under the fuse box. I eventually pulled the forward circuit breaker in the box and it stopped. When I put breaker back in it continued. So then I pulled the first fuse(5 amp) and it stopped again and did not continue once I replaced the fuse. But now the battery appears to have enough to run lights and such but when I go to start car....nothing dead but lights still work?? Maybe I have the same problem? Any ideas??
#6
10-15-2009, 07:44 PM
UPDATE: While having dinner, about an hour I had the car on the charger. Not a big heavy duty one, just slightly larger than a trickle charger. Anyway the car started on it own, ran for several minutes then it all started happening again. I shut it off and now it won't restart so its back on the charger.......
#8
10-16-2009, 10:45 AM
Vette, when your car starts acting funny, measure the voltage across the battery terminals with a multimeter. I've got some experience working with automotive / mobile equipment ECUs (electrical engineering) and I know a lot of them will start acting funny when their power supplies drop below a certain voltage (usually around 9 or 10V on a 12V system). I think that was part of the problem on my car. I don't think the charging system was working 100% because it's controlled by the BC1 module. So when it would dip down below 9 or 10V everything would start acting funny.
Anyway, the problems you're describing sound VERY similar to mine before my car took the big ****. Specifically the warning lights flashing on and off at random, gauges not working, and headlights flashing on and off erratically. The BC1 is located behind the passenger side kick panel, underneath the hood release. There's 4 connectors on it, a white, black, blue and green. I've read some accounts where people have had luck pulling these out and taking the cover apart (6 snaps you can undo by hand) and then gently blowdrying it. As far as where the water's coming from, the sunroof is what the dealer told me, but I trust them just about as far as I can throw them.
I don't know if I'll get away with spending $115 and fixing my problem with a used BC1, but I'll definitely let you know if it works. Either that or $460 unit from the Mini dealership. So to sum up, here's what I've learned so far from the dealer parts guy, a company that does reprogramming, and random research that may or may not be accurate. Hope this helps!
-Need to match Year, Chassis type (yours is R53 which is '02 Mini Cooper S), and part number of BC1.
-BC1 has a white tag on the front, the lines look like this
BC1RD R50/53 12V --->body control 1, R50/53 chassis, 12V power
MINI 6 961 363 AI01 --->I think this is the number of the unit made, maybe a date code
577 621 10 DELPHI DE --->I believe this is the key number to match because I've come across multiple BC1 modules with this same number
HW 1.4 SW 1.4 510400 --->Probably hardware and software version numbers
Like I said, there are a bunch of these on www.car-part.com, will let you know if replacing it works.
Later!!
Dave
Anyway, the problems you're describing sound VERY similar to mine before my car took the big ****. Specifically the warning lights flashing on and off at random, gauges not working, and headlights flashing on and off erratically. The BC1 is located behind the passenger side kick panel, underneath the hood release. There's 4 connectors on it, a white, black, blue and green. I've read some accounts where people have had luck pulling these out and taking the cover apart (6 snaps you can undo by hand) and then gently blowdrying it. As far as where the water's coming from, the sunroof is what the dealer told me, but I trust them just about as far as I can throw them.
I don't know if I'll get away with spending $115 and fixing my problem with a used BC1, but I'll definitely let you know if it works. Either that or $460 unit from the Mini dealership. So to sum up, here's what I've learned so far from the dealer parts guy, a company that does reprogramming, and random research that may or may not be accurate. Hope this helps!
-Need to match Year, Chassis type (yours is R53 which is '02 Mini Cooper S), and part number of BC1.
-BC1 has a white tag on the front, the lines look like this
BC1RD R50/53 12V --->body control 1, R50/53 chassis, 12V power
MINI 6 961 363 AI01 --->I think this is the number of the unit made, maybe a date code
577 621 10 DELPHI DE --->I believe this is the key number to match because I've come across multiple BC1 modules with this same number
HW 1.4 SW 1.4 510400 --->Probably hardware and software version numbers
Like I said, there are a bunch of these on www.car-part.com, will let you know if replacing it works.
Later!!
Dave
#9
10-17-2009, 09:48 AM
Dave, Thanks for the answers! After I fully recharged the battery all seems normal again. Even when I load the system with bright lights, etc, trying to get it to fail. This same thing happened 2/3 weeks ago and I bought a new battery at that time. I wonder if there is a way to seal the area where the BC1 is located and maybe this will stop happening??
#10
10-19-2009, 11:37 AM
Anyone got any recommendations where to take this car to for this electrical repair in the Quad Cities area???