Hi. I'm a long time BMW CCA member (currently have a 2002 M3 Coupe) but new to using the Forum. I am right now dealing with a 1991 850i that has (temporarily) come into my care at www.m37auction.com (a consignment auction business near Grand Rapids, MI) where the car will be in our next auction at a very reasonable reserve. The battery had gotten low so I took it out to recharge it (being careful not to latch the trunk lid) and when I reinstalled it I noted that the owner had installed one of those green knob cut off switches so I decided since the car is sitting so long that I'd keep the knob in the off position, closed the trunk, opened it with the key (as described in the manual) so thinking all would be fine I again closed the trunk. Dumb! Key now won't open it and with the battery disconnected no way to attach a charger or jump battery to the terminals under the hood. I'm thinking that a possible to solve this is to pull the back seat out and hope that will provide a way to reach in and turn the green knob to the on position.
Welcome to the forums! see if any of these help: http://forums.bimmerforums.com/forum/showthread.php?410317-850i-E31-Locked-Trunk http://forums.bimmerforums.com/forum/showthread.php?1435713-Dead-battery-How-do-I-get-in-the-trunk http://forums.bimmerforums.com/forum/showthread.php?1839503-Dead-battery-how-to-open-trunk Parts 15 & 19-21: http://www.realoem.com/bmw/showparts.do?model=EG23&mospid=47335&btnr=41_0087&hg=41&fg=60 From the suggestions in the above threads and assuming the parts diagram echoes its installed position, it sounds like there is a key-actuated mechanical push-button trunk-catch release positioned vertically, and normally completely out-of-view when the trunk is closed, but presumably viewable straight-on when the trunk is open. Bend down and take a look at what's there - the suggestions in the above threads seem to be to insert key, turn, and remove the key and push the button, or leave the key inserted and turned, and push, which presumably mechanically releases the trunk-latch.
Through the back seat might work. You know that there are 2 batteries, right? one on each side. Battery charger connected under the hood maybe would activate trunk lock.
Also, one of the threads mentioned connecting some power into the car via other points and having some success, possibly in conjunction with the trunk key lock.
I agree with terry that you should put a jump box under the hood jump posts and see if it gives power to some of the car.
Thanks to all who responded. I simply wasn't pushing up on the tumbler firmly enough. Gave it a firm push this morning and it popped right open (duh). The car indeed has two batteries altho the right side one is a challenge to access with the CD Changer over there. For the record with the left side battery disconnected attaching a jump box to the under-hood posts didn't appear to provide power anywhere. Fascinating car. The consignor has dropped his reserve to $6500. Tempted. manley776@yahoo.com
Alas, Satch, no six speed in this one. Nice car for the price tho. Seller today indicated he will sell this car for under 6K. I have a potential local buyer who if we can work out a deal will certainly be a new recruit to CCA. -Manley