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-   -   Doors Locked - Battery Dead '93 740i (

CMarzotto 03-02-2012 02:33 PM

Doors Locked - Battery Dead '93 740i
I have a '93 740i that has been sitting in front of my house for a couple months. The doors are locked and the battery is dead. I usually could get into the car by lifting the door handle and turning the key, but that seems to be worn out and won't work. So I can only access the trunk and need to get some power to the car in order to unlock it and access the battery for a jump.


1bad540 03-03-2012 06:06 PM

Turn the key all the wzy to the right and then push it a bit more, should pop the lock

Foote 03-05-2012 05:13 PM

I'd rather not start a new thread with a similar problem, but my '94 740iL has the same problem. I managed to scratch up my interior with a fork taped to an umbrella trying to unlock it from the ski bag, but no dice.

I've tried turning the key and popping the handle over and over and I've got nothing. I was told there was a square spot on my rear bumper where I can jump it but all there is is a tow hook.

TerryY 03-05-2012 06:37 PM

Are you using the key on the drivers or passenger door lock? IIRC only the passenger lock has the emergency over-ride.

Foote 03-05-2012 06:39 PM

Me, I've tried both. Mostly drivers, but I've tried passengers enough times.

TerryY 03-06-2012 02:41 PM

This is a good page to have bookmarked

Unfortunately the links to your problem seem to be expired.

I understand that the effort needed to activate the unlock on the passenger door is enough that you will think the key must be about to the breaking point.

It also may be possible to jack up the car and jumper to the large connection on the starter and what ever ground you can find on the engine or body.

Foote 03-06-2012 07:15 PM

Lol speaking of which, I had tore the plastic on my key trying to force it into all the directions. Thanks for the link, I can't seem to find anything right now but I just got the owner's manual for the 7 series. I'll post any solutions I find.

alpinaman24 07-30-2012 12:56 PM

jack up the car from the driver side put a booster to the starter power wire and a good then try the key

fidolido 06-16-2014 04:57 PM

Put key in passenger side, pull handle up, turn key clockwise..... should open.

BMWFatherFigure 06-25-2014 12:16 PM

I got in with the 'power to starter' trick on my E34. Then I CHARGED THE BATTERY and the problem went away......

Narly9999 07-31-2014 03:53 AM

I put jumper cables to the light in the trunk. Positive to the light bulb contacts with bulb in place. Ground to the body metal. Gave enough power to unlock via key in door.

Sent from BimmerApp mobile app

bmw-mania 07-31-2014 08:20 AM

Thanks Shogun!


Emergency access to a car with a dead battery

Do I have to sell the car?

The trunk always opens with the key, no matter if the battery is completely empty or there is no battery at all in the car.
Trunk light is best, this is what Tim once wrote:

unlocking doors via trunk light connections

The emergency unlock (lifting the passenger door handle and then turning the key over a certain resistance) sometimes does not work.
However, even with a dead battery the trunk can be opened with the key by turning it anti-clockwise and then push the unlock button.
To avoid wrong connection of power to the wires or blowing the fuse, Timm from the 7 series register in the U.K. has made a nice write-up:
A few pointers to connecting power to the boot/trunk lamp:
Firstly, the boot/trunk light is a good place to connect power as it is constantly connected to the battery via Fuse 33.
However, you must only use a charger at this point, and only one that can supply a maximum of 10A.

If you use a fully-charged battery you will blow Fuse 33.

The boot/trunk light has two wires going to it, RED/WHITE is the positive supply, connect the chargers +ve terminal to here.
Connect the charger-ve lead to somewhere on the chassis.....this removes any possibility of reverse polarity.
When the charger is connected and charging, allow 10 minutes before trying the central locking, this is just enough time to get enough charge in the battery to supply the locks.
If you have not got a charger you can use a battery but MUST connect it via a 55W (headlamp) bulb. This reduces the current to a safe level.
DON'T connect to any other lighting point, these go via the LKM or General Module and it is not a good idea to stuff power up these!

cessnaman 08-01-2014 06:01 PM

i have a 94 740il, tryed all those things, other than a very very small person, was impossilble without breaking glass,,,,,,, passenger door key lock to unlock was in, two stages ,turn key to unlock , lift and release handle and continue to turn key should open when lift handle again, kinda like a puzzle lock,

xladlk 10-17-2014 01:25 PM

Hood Open, Charger On, Doors STILL Won't Open
AAA finally got the hood open on my '94 740iL and even though the charger has been running for several hours, doors still won't open and the charger doesn't even recognize that there is a battery in the car. The car set for 6 months so we are talking DEAD. (Should have disconnected battery before leaving town but forgot.) Left window cracked so TX heat wouldn't break glass so we can get wire on the door lock but neither myself or AAA could get the door lock to pop open. Have popped them open with key/door handle combo on several occasions but not this time; even connected to charger.

Any other suggestions on how to get in so I can yank the old battery and install yet another new one which would make my 3rd in 2 yrs. Some day I might learn.


TerryY 10-17-2014 10:02 PM

Have you tried connecting a good battery with jumper cables to the posts under the hood?

xladlk 10-17-2014 11:04 PM

Technically "No" but
Besides the fact I didn't have any "good" batteries laying around, I figured the charger was sufficient but tomorrow I can try a jump from my truck. Thinking about it now, these new and fancy chargers may not put out anything if they don't detect a battery present. Good idea to try, thanks.

BMWFatherFigure 10-29-2014 12:40 AM

Invest in a floating / smart charger. I run 4 of them.

total3nz 11-04-2014 02:12 PM

My 735i had the same prob...Did the the turn key to breaking point and got the misses to operate the remote at the same time and up it popped...whether it was the remote or the key we will not no....just my few cents worth.....

xladlk 11-13-2014 09:33 AM

"Smart" Charger was Too Smart
Using a long hook through the partially open window, we were able to pop the hood release and hook up the charger but still nothing. Turns out my "smart" charger wouldn't send any current as it did not detect a complete circuit due to the battery being completely shot. Jumped the car from the truck and viola, doors unlock. Car still wouldn't turn over with the new battery due to a blown fuse for the OBC but replaced that and started/runs just fine.

Next time I leave for an extended period, I'll disconnect the battery. (Thieves would just steal a battery tender.) Thanks for all the good suggestions. :)

BMWFatherFigure 11-13-2014 05:46 PM

Lock the battery tender in the trunk (boot) on a heat sink

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