I just bought this 300SD a few months ago and have witnessed the trunk open. For some reason the trunk won't open for me. I know that the key hole must be in a horizontal position. I do not have a vacuum leak, either. What's going on here???

I am not trying to insult your intelligence. I just don't know what your knowledge of the Mercedes is.

The part that the keyhole is in is a button. Push it in to open the trunk. If it doesn't push in, it is not unlocked.

I'm aware of that. Still no luck. Isn't this the strangest thing???

Same caveat as from 'Q' above --

On my W124, the key slot must be in the VERTICAL position for the button to work . . .

Again, not to insult your intelligence, but I have seen this happen many, many times. Folks try to raise the trunk by lifting on the trunk frame, rather than the trunk lid itself. Make sure that the lock button engages, then lift only the lid.

__________________
'76 240D-Sold
'78 240D-Sold
'85 300 SD, 165K-Sold
'88 300 TE, 165K-Sold
'64 Porsche 356C Cabriolet- under restoration
'86 560SL 124K Miles-Sold
'94 320E Wagon, 74K Miles-128K Miles JUNKED
'06 E350 Wagon, 84K Miles
07 SL550, 14K Miles

I had this happen several times on my 83D. I even had to help a lady in a parking lot get her MB trunk open.. she said it was aggravating at times. I have no sure fire formula but here is what I did to get my trunk lid open--- Insert key (horiz. position); turn left (counter clockwise) putting the position to vertical; with key still inserted, push button in; if trunk does not "pop" open, continue hold key/button in and with your other hand lift gently on the trunk lid. If this doesn't do the trick, then insert key again (horiz.) then push in and then turn counterclockwise, try lid; if failed, then continue to hold key pushed in.. in vertical position, release pressure to allow button and key to come to "out" position, then push in again on key and button and try lifting trunk lid with other hand. (boy, if you can understand these instructions, you're a genius) I had to try the various options that I described and then just "use the force, Luke" to "feel the moment" between key, button, and hand. Mine always opened though.. never had anything done to fix it.. just some days it opened normaly and others it was "abnormal". Good Luck.

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Nello Tare

1982 300D (266,001 mi.) looking and running great

Previously owned:
1976 450 SLC
1983 300D
1976 300D
also
1982 Jaguar XJ6 (loved, but gone)

I have w123, w124, and w126 and I never can remember which model has vertical or horizontal for unlock because they are different.

When the button is in unlock position, try to push the button with the key inside the lock. I have seen that problem happens to some MBs (including one of my cars ). Another problem I saw was that the trunk was actually unlocked but needed a strong lift from the owner (lift the lip as Ron indicated). That is due to rust or sticky latch.

Good luck

David

Perhaps you are trying to open the trunk with the valet key. If the key is an original Mercedes key and round it is the valet key. It will not open the trunk or the glovebox. The square key will open everything. I may be wrong.

I would also think that you should unlock and lock your doors to see if your vacuum unit is locking and unlocking the trunk. You can hear it.

"Open sesame" did the trick for Ali Baba.




ps. Hope your trunk works with all the wonderful advises here. Do try not to open your boot with your key as you may confuse yourself when it doesn't open in future.

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... Kerry

126 tailed by a 203, 129 leading the pack.

As a last resort, there is an emergency trunk release cable that is located under the rear passenger seat on the left side. Pull straight up on the seat cushion and it will snap out of its lock position. The cable is in a plastic sleeve and has a loop on the end. Pull on the cable to release the trunk latch. If it still does not unlock, pull on the cable while a helper trys to open the trunk. Good luck.

My thanks to everyone here! But I have one question: What do I do to eliminate this problem? Getting the trunk open isn't going to fix the exsisting problem. I assume that I'll have to get a new lock mech?!?! Who knows?

The last thing Mercedes lovers want is to be seen having problems in a parking lot or get caught with our "Pants down" with friends and/or family around. I get enough "guff" from my brother (Mr. Ford Designer) for owning a foreign car (...the close minded booby-drives a 99 Taurus...yawn!!!)

It never ceases to amaze me what a little lubricant will fix.

Your problem may be the vacuum control device for the trunk locking system. To check, remove the metal plate located inside the trunk and near the lock. One or two screws hold it in place. The vacuum element will then be exposed. Pull off the vacuum hose connected to the element and check with a vacuum pump to see if it holds vacuum over time. You can buy a pump at Auto Zone fairly cheap. You can also try locking the car while keeping the trunk open. Come back in a couple of hours and unlock the car and see if the trunk lock vacuum element also released. If it doesn't then you have a leaky diaphram.

This problem has happen on my 300E, there is nothing wrong with the vacuum or the key positions. After the trunk is open with a little gentle lift, put a little lubrication into the lock. I don't think it will happen again.

jack

I've just printed all of these great ideas. I told my brother today, during lunch...come "hell or high water", I WILL get that trunk (boot) open this weekend. I will let all of you know of my progress on Monday...wish me luck!!!