2001 E46 M Coupe.

The car's about to go back on the road after not needing for commuting
for most of this year, so I was a shocked to find a wet passenger foot
well carpet.

Feeling around for a source path, imagine my shock when I opened the
glove-box, and found it very wet, and then opened the fuse box and water
actually came out from within the plastic cavities that the fuses sit
within!

Apart from washing the body occasionally (never used a jet-wash), and
moving back / forward to avoid flat spots, the car hasn't been touched.
The battery is off and garaged, so no electrics on.

I've been all over the Web but no mention of water in the fuse-box.

I've had the car 7 years, and have noticed that the windscreen steams up
fairly easily, but assumed it was just as it was ventilation-wise, as
I've never found wet carpets etc.

It's not had a new windscreen to my knowledge, nor have the door
cards/seals been off. I have noticed a couple of splits in the
windscreen surround, both sides of the car (drivers side is definitely
dry), but I think these are more cosmetic, the screen bonded underneath?

The car sits underneath a hawthorn tree, so I've cleared some small leaf
reside from all the gutters etc that I can see under the bonnet and
also from within the cavity that the rectangular filter sits within
underneath the central bonnet grill next to the windscreen.


Are there any known drain holes / channels that I've missed that block perhaps?
Does anyone know of any other possible causes?

As the fuse box is wet, I can't re-instate the battery and use the car.


Thanks you to anyone who can help!

I cleaned all the places, gutters, etc under the bonnet yesterday hoping that I was solved. However, after a night of heavy rain I've found that the A pillar is actually wet, almost from the top.
Hhhmm, dare I risk trying to get the A pillar cover off, bearing in mind there's an airbag in there?
Not sure what I would find / be able to do re fixing a leak? Is there a sealant inside maybe?
The car doesn't have a sunroof - Googling shows a lot of people get leaky sunroof drains.
The windscreen appears to be original as it has 'BMW' on it at the bottom.

Does it have a sunroof?

You'll be okay to remove A-Pillar trim etc. Just disconnect battery first ;)

Is it collecting water as its stood or moving?

Hi, the A pillar cover off, the metal wet through from the top corner at the roof junction. Can't see any perforations etc.

Car's standing by the way.