Key is stuck S500 1996
 

Hello

My car has been sitting for two weeks and when I should unlock it with the remote the doors were not unlocked. So I opened the drivers door manually with the key. OK. Only problem is that I can not get that darn key out of the lock! It is stuck and of course i can not start the car. ????

This is maybe caused by a bad battery. Unfortunately i parked the car so close to the wall it will be very difficult to open the trunk! Is there any jump start connections in the engine bay??

Any help appreciated!!

Not certain where you battery is located. In my E class it is beneath the rear seat.

There should be a + battery stud in a 2" x 3" plactic cover with a red + on it inside the engine compartment. On mine it is close to the drivers side fender. You have tto find your own ground point.

The mechanical key has nothing to do with the battery, perhaps by getting some lubricant to run down the key the tumblers will free up

Yep, that's what I was thinking.

I'd spray in some WD40 and / or graphite lubricant and wiggle the hell out of it.

Strange system
 

The big issue here is WHERE CAN POWER BE APPLIED in the engine bay area or in the coupe in w140. I know that at least in my car there is not possible to go into neutral with the gear selector without power. It is locked. Regarding the key: This has happened once before and then it was released by pushing the radiobutton or central lock button. (my father did it and hen dont know which button it was). But this time there is no power. Also it would be very interesting if someone could explain how the vacuum locks are designed and why Mercedes chosed them before electrical. Thanks!

Far as I know, in a 140-chassis car, there are no connections under the hood for a jump start.

On my car ('92 300SE) the mechanism to release the shifter from park isn't electrical, it's mechanical. If you can get a key into the ignition, turn it to the 1st click, press the brake pedal and shift the car from park.

I have no clear answer as to why MB chose vaccuum for the door lock system, but I know that they've been at it a long time. My dad had a '75 280 and it had vaccuum locks, but there was no pump like in my car. There was a reservoir in the trunk that stored engine vaccuum and that supply was good for several actuations of the locks with the car off. After the vaccuum was exhausted, you could still get the doors open, but the central locking feature was gone until you started the car again.

In the 140 chassis cars, there are tons of things that are run off the vaccuum/pressure system. Door locks, rear headrest retractors, lumbar supports, reversing aid masts (only on 92/93 cars, I think), trunk lid handle, trunk closing assist (only used to help extend the retractor pawl), manifold vaccuum assist for the ventilation system, trunk release. I'd guess that the pump that does all that draws far less electricity than separate electrical devices would to do all those jobs.

Both problems are now fixed. I used the other key to get power through the lighter and by that it was possible to push the unlock button and open the trunk. I connected a battery to the old battery and started the car. But it did not start, only turnover. I had to lock and unlock with the IR key as well and after that the engine could be started. The key stuck in the door got loose after some bending and pulling. I strongly recommend you gentlemen to exercise these locks once in awhile. Also I found that the new S/class has the battery in the trunk and a additional battery in the engine room. Maybe Mercedes has learned something.

The W140 has no engine jump start points because MB does not want you to jump start it on the first place. Actually, the owner's manual on my car (Euro version) completely advises against it.

If your battery is dead, they advise to charge it (without the car cables attached) or replace it.

Jump starting a W140 at least raises the chance from frying your alternator solenoids up to burning all electronics/computers.

I tend to agree with this. A tow truck and a battery are a lot cheaper than a few $500-700+ computer modules that your kill in the process of a jump start.

If it were my car it would be on a flat bed key and all on the way to my mechanic. Let him figure out the key issue and replace the battery on the car too.

As for the WD40. The W140's are as much a rolling computer as anything else. Would you shoot WD40 into a computer because of stuck media with the power on?