I didn't see any posts concerning water in the 2004 MCS R53 battery box in the boot. Has anyone else discovered this issue? and what did you do if anything to stop the Boot from leaking?

 

Pretty common...
Look around....
The gasket on the 3rd brake light is common, as is the boot gasket having been folded over, etc.

 

...or the body shop didn't install your back window correctly so it leaked.

Oh. Sorry, that was my car. Nm.

 

I would look into that but my Baby is a 2004 and the leak just appeared this summer. thanks for the suggestion though.

 

I will look at my third break light as the boot gasket looks fine to me.

 

wiper grommet was where I had water coming in at.

 

ok i will look there as well thanks for the info.

 

Seems to be a pretty common issue. I had the same problem, battery box filled up with water and shorted out the fuse on the battery terminal. Tried the 3rd brake light replacement, water still coming in. Put some silicone above boot handle/license plate area, water still coming in. I eventually removed the boot gasket and filled it with silicone before putting it back. No more water since. The gasket got crushed with wear and was no longer creating a tight seal. So far so good. Water was coming in after a rain storm every time. Now it's dry.

 

Check the Third Brake Light! This fall my '02 MCS started leaking into the boot. During heavy rain I would get water streaks on the inside of the rear window glass and my carpet would be damp. For a quick check I put clear packaging tape over my third brake light, no more water in the boot. This will keep things dry until I can get a new gasket and install it.

 

Just remember...
if you were pretty agressive with a high pressure water hose, water can also get in around the rear brake lights...
They are held in by one bolt, and have free space around them...when new they usually have a thin foam strip that keeps incendental water spray out...but direct will always get in.due to the angles, it is an unlikely scource, but with hoses, carwashes, etc, anything is possible.

 

Thank you all for your awesome suggestions. I am going to exlpore them all. up untill now My solution was not to drive her if even a threat of rain and would vacume out the water after a wash. I will let you know which it was.

 

Seems to be a pretty common issue.

 

I wanted to add that on my 06, that the third brake light housing was actually starting to separate and water leaked in recently. I pulled the lens off the housing and resealed it with clear silicone and installed a new gasket.

 

thank you all fot the info i am going to look into all these suggestions.