Not sure what they are for but water was definitely getting in there. Tightened the bolts facing the trunk and I didn't notice any difference with the hatch closing.

I will modify my semi-annual check "Pano-roof drain verifivation" to include inspection and tightening of the electrical boots and rubber stops. Yes, I have this as a maintenance check; based on the serious "water" problems documented in this forum.

Looks like I have the same issue. A ton of CAN communication error codes, ABS/EBD/DSC/4x4 lights, etc.

Here's what my trunk area looed like. Hopefully replacing the ATC700 module and sealing whereever the water came in does the trick. Thanks for sharing mart_dev!

Soaked trunk area
http://img.photobucket.com/albums/v1...psrvljorxm.jpg
Water on Battery terminals
http://img.photobucket.com/albums/v1...psgdr7imeu.jpg
Water under battery
http://img.photobucket.com/albums/v1...psxhomlpoo.jpg
Right side compartment
http://img.photobucket.com/albums/v1...pspyuhoeuf.jpg
Left side compartment
http://img.photobucket.com/albums/v1...ps9vj1f90h.jpg

Upadate for anyone interested, I replaced my ATC700 Transfer Case Control Module with a used one and everything works fine now. Seems the water fried the old one. I just unhooked the battery, replaced the module, started the vehicle, turned steering wheel full lock to lock, and codes went away :)

Yes, in my case it was the sunroof drainage. they are located on top of the trunk, next to the hinges (there are two, left and right). There are to black rubber thingies with a tinny door attached to it (the first pic in the thread) . I just use a long wire to clean the passage and it did the trick. It was a nightmare to figure it out the leak,but I'm glad is gone.I had same symptoms as mart_dev.

Old but so much helpful post I'm glad I came across it. My PDC's are currently not working, all of them. This happened after I went to a car wash, the very same day I had noticed that there was water splashed around the Fuse Box and cables were all wet, this got me worried. Until I came across this Post then I went straight checking. Guess What, the right side upper seal underneath the drain was wide open, all the water draining directly into the car. So in my case I suspect this killed my PDC module and possibly my Rear Fog Light that only works when I punch the light with a fist. So I clipped it back and I will monitor these all the time I go to a car wash. Bad Design BMW!

Now need to run some Codes and verify if my Module is dead or it's cabling!

Attachment 76310
Attachment 76311

Ok after reattaching the water seal, I decided to dismantle the boot, as per images attached and there it was, a pool of water with all the cables swimming in there :( . Got it all drained. Then I decided to remove the Parrot device that the previous owner had installed draining my battery. All seem ok at the moment. Just wanted to check with U guys if this is a AGM battery and if not, how do I check that?

Attachment 76318
Attachment 76312
Attachment 76313
Attachment 76314
Attachment 76315
Attachment 76316
Attachment 76317

That battery is not an AGM. The label says 'Flooded" right on it.

Thanx I suppose I need to get a New Battery :(