Hello,

I just purchased a 2004 S and did so knowing it had some potential issues. It's electric blue manual btw and look forward to putting some miles on her this summer! The previous owner started there was water from the sunroof which corroded the BCM pins and connectors. I have done some searching, but not came up with the answer I needed yet. The passenger is locked and central lock will not unlock it. Sunroof and radio do not work. All other electronics function as they should. I pulled the connector to the BCM and there is corrosion on the small connector. I have seen where some hardwire and by pass connector, replace BCM altogether (I am hours from a dealer so programming would be a pain), or swapped out for a used BCM. I hoping someone can let me know if the exact issues I have sound like the BCM? I assume so, but I know there are other electronics on that side of the car. If it is the BCM and connectors, are there any companies out there that transfer data ect? Any input would be greatly appreciated. Thank you!!

 

The pins can usually be cleaned . The connectors can be replaced or splced with used one. check ebay

Does it make a noise like its trying to unlock it ? you may need a new lock assembly. The motor for it gets full of crap and cannot open .

http://www.instructables.com/id/Repa...ck-Actuator-L/

Do you have an ipod adaptor installed these are known to cause errors in the communication system . This will stop the radio and sunroof from operation.

This happens to mine all the time ...just unplug it.

 

Your symptoms are classic rain roof damaged BCM. When the rain water intrusion is bad and long enough, corrosion can occur on the BCM circuit board. In that case repair may involve repairing PCB traces, or replacing integrated circuits (ICs). There are a few owners with the skill successfully repair damaged BCM components.

 

Thank you both for the replies and suggestions. I picked up a good used set of BCM connectors as a majority of the corrosion seems to be centered on one connector. I may just splice that in, clean all pins, and see what happens. Thank you both again and if you know of anyone who repairs BCM's that would be helpful information. Thanks!

 

Greetings all!

I would never want to improperly hi-jack another thread,,,, but I just need to know an answer. I too, am concerned about the poor placement of the BCM on my 2005 r53. Now, I have only opened the sunroof less than a dozen times in 14 years ( I did open it recently to inspect for any issues...luckily the tracks were spotless..). So...should I be concerned about the mysterious drain tube (tubes?) receiving proper cleaning? My BCM gave me grief about 8 years ago...a brake light issue, but has since operated flawlessly, without any needed replacement.

I so apologize if I am breaking the house rules by hi-jacking.


Best,

Monkey Juice

 

Interesting that after looking at a wiring diagram the connector that's corroded does not have functions for the sunroof and radio. I have checked for an ipod adapter and see none. Makes me wonder if this is truly the issue. I have checked the fuses and they are good. Damn wiring stuff! Ha! Any input would be appreciated! Thanks again everyone!

 

The drain tubes have a habit of coming loose from the sunroof cassette. I would check the drain tubes before replacing the BCM and add hose clamps to secure the tubes and hopefully prevent future issues.

Here's a post with some info: https://www.northamericanmotoring.co...-footwell.html

 

Thanks for the heads up. First thing I did was take care of the drain issue. I very much appreciate the comment and link though!!