I would have your sunroof drains checked and the all the rubber window seals - rear window, side windows and even the windshield. If water gets in behind a window seal it can pool on the floor of the car.

 

Yes all the window rubbers, sunroof drains, and seals are about to be checked. Today, the carpet comes out, which means taking out the seats and centre console, just to access the modules under the rear foot well. Last week, after discovery of water damage to the power module, which is in the e-box under the cabin filter in the engine compartment, the module was replaced, but there was still no power to the engine control modules, which meant no start. It seems that the water had filled the e-box, and found its way down the wiring looms to the cabin, and pooled in the rear foot well. Does anyone have a link to show wiring loom diagrams, locations of computer modules, in particular, under the carpet? What are the part numbers for those modules? And any links to similar information to the apparently common water damage problems in 2004 645Ci E63 models would be appreciated heaps.

 

.... And any links to similar information to the apparently common water damage problems in 2004 645Ci E63 models would be appreciated heaps.

The only "common" 6 series water damage issues are problems with the convertible models. The drains in the top storage compartment can get clogged and this causes water damage to the amp/NAV rack in the trunk.

I have never seen someone complain of water issues on a coupe during the last 2 years that I have been reading this forum. I have never heard of water getting into any of the modules under the hood ever, and I've owned BMWs since 1996 so that is a rare occurrence.

 

This should give you what you need. The 1st link is electrical & the 2nd one will be mechanical.

Good Luck

http://wds.spaghetticoder.org/en/

http://tis.spaghetticoder.org/e63/645Ci_(N62)_COUPE/

 

Thank you Herb, Those links look very useful, much appreciated. "Spaghetti" is an appropriate word here. Cheers, Bryan

 

Just an update on progress, the water had entered the e-box through the seal between the e-box and firewall. To be more specific, the e-box is a 3Litre sized plastic box under the cabin filter area in the left rear side of the engine bay. It contains the Power Module Unit and the connection junctions to the wiring looms going into the cabin. Theoretically, it is exposed to the cabin atmosphere through a hole (for the wiring), which is sealed between the firewall and itself, "the box". And theoretically it (the box) is sealed from the exposed weather and water draining passed it from the windscreen area. If water gets into the box as in my case, it first destroys the power supply module, then travels down the wiring looms into the cabin, eventually soaking the computer control modules under the carpet, one of which is the active steering module.

 

I was just thinking about your issue. For water to get into that compartment, the lid would have to have been removed or dislodged from a passenger side impact. My car has a lid on this fuse box. I dropped a screw looking for it, & I found this compartment. The only other way would have been if the car had been flooded? I agree that once water gets into this fuse panel, you are screwed!

Good Luck!

 

Wow sorry to hear about that. I've never seen the module box out in the engine bay leak since it is sealed very well.

 

Thanks, I guess there is always an exception to normal. To clarify, yes the e-box was well sealed and lid was on OK, but to describe better how it got water into it... i have to describe it better for those who haven't had the pleasure of experiencing this misfortune, it is mounted flush hard up against the firewall left side, in the rear of the engine compartment. You can't see where it is, until you remove the cabin filter housing just under the windscreen. Where the e-box touches the firewall, there is a hole tunnel through to the cabin for the wiring loom to enter the cabin area behind the glove compartment. That tunnel/hole "entry-way" normally is sealed around it's perimeter, but in this case the seal was parted, allowing the rain water (that normally drains down from the windscreen in a channel past that area) to enter the tunnel and e-box. So much water had entered there was a tide mark in the e-box up to the level of the hole. The Power Supply Module and loom connectors in the e-box had been submerged in water. Also the water could travel down the wiring loom into the cabin and fill the floor wells both sides, submerging the Computer Modules under the carpet. No wonder, (after being parked up long enough for this to happen) that the on-board-computers through so many fault warnings up on the I-Drive Screen when I first got back in to start it up, and didn't respond to engine start attempts. The car is still stripped apart, drying done, Modules being replaced, electrical connectors cleaned, ready for assembly and fault clearing etc..... lots of fun and money :-( I miss my black beauty

 

Wow! this is just bad luck! There are drains for that compartment area. Make sure to remove all debris to try & help this from happening again!

God Luck!

 

so how did u repair the leak,i'm having the same problem

 

645 going to waste

Thanks shranda for your question - I have not been on this forum for a while. My name is Bryan Hopwood - from New Zealand. The issue with water damage in the BMW 645ci was sorted as i thought. The service agent here in New Zealand did a $2500+ worth of labour charges to strip the car interior, dry it all, replace one computer module (extra charge), and clean the contacts on the others that got wet, reseal the e-box against the firewall, clear the blocked drains from that box, and assemble it all - and seats and carpet back in. What a shambles. The car went OK for 2 months. Now I have parked it up again because now it has heaps of new errors showing, and no start - no starter motor action. I have had 3 BMWs and dozens of other brands. My BMW was a quarter million dollar car and can't even live in the rain without dying, and can't even see the sun without fading, and can't even go through a carwash without scratching. Ironically, my other 10k hacks can go through 100s of car washes without a scratch, sit in the rain for months, or sit in the sun for months, and still look good, and still start every time. Damn I am so disappointed with the silly over computerised self disabling modules on this BMW. So it stays unused, a black modded 500hp hamann kitted beauty with all the options, sitting in the paddock, totally useless, as I enjoy my older hacks. Vent over !!! Now I feel heaps better. Cheers - Bryan

 

I'm getting a leak in the same place,i can see where the water is coming in the car. I was just wondering if this is a DIY project..i'm going to put the car on a lift tomorrow to see if I can get to the Grommet..maybe I can remove the plastic computer box and access it that way:thumbup:

 

If the carpet is wet in the rear passenger's foot well area, there is a computer module under that, just at the lowest point where water will pool there, regardless of how the water entered the cabin. It is a large job to access that module if DYI. The seats, centre console, etc and lots of things have to be removed just to lift the carpet. If you are lucky and the module is not damaged, and no errors yet on the display, you could try to dry it all and fix the cause of the leak. The cause of leaks in that model are sometimes the sunroof seals, sometimes the upper door rubber folded wrong when door closes, and in my case, the seal between the e-box and the cabin firewall where the cables enter the cabin from the engine compartment, was not sealing. This allowed water to enter the e-box, and then also debris blocking the drain in the bottom of the e-box. When the level of water in the e-box reached the entry level into the cabin, it runs down the cables and into the carpet area. Awful design, and big job to fix.

 

Hi Everyone, after owning my 645 for 3.5y, everything is great guess what, I just have the exact same problem with the water issue that cook my active steering control unit, it going to cost me upto £1k, beware check the blockage on the 2 box in the engine compartment, I did clear it out 1.5y ago just didnt expect it block that quickly, well I learn my leason.

 

I think the way the car design or as big as BMW could do a lot better, like these easy blockage groument, reverse light bulb access, head light access, electrical senstive issue etc. doesnt do the car any good.

 

yes, there are many areas to trip you up in these cars. For anyone interested, here is a previous thread regarding clogged drains under the microfilter. Along with info on how to access them.

http://www.bimmerfest.com/forums/showthread.php?t=679976