Trunk will not unlock - PeachParts Mercedes-Benz Forum

Roncallo · #1 10-01-2007, 06:06 PM

Gentelmen

On my 1996 129 which has no electrical system, I can not unlock the trunk. I can turn the key and push the lock but it will not unlock. This all started when I was in the process of removing all electrical from the trunk and I removed some kind of actuator which in hind sight is mechanically connected to the lock.

So what are my options. I looks like I can see some kind of mechanism through the licence plate lights which are removed, but I canot figgure out what to do.??

Thank You
John Roncallo

Pete Geither · #2 10-01-2007, 10:25 PM

I have been pondering this question and looking at my car to help find a solution. I think you are in deep $hit. We have had this problem mostly with Honda doors, and the only way we have found to open them is to air chisel around the latch mechanism, and then apply brute force to the latch itself. It isn't pretty.

Hope you can find a better way.

Roncallo · #3 10-01-2007, 10:38 PM

Right now its looking like breaking through the third break light may give me acess with minimal damage. Anyones thoughts

John Roncallo

wscheffer · #4 10-02-2007, 02:52 AM

Drill out the lock cylinder then use a screw driver to trip the lock mechanism.

Roncallo · #5 10-02-2007, 08:04 PM

Quote:

Originally Posted by wscheffer

Drill out the lock cylinder then use a screw driver to trip the lock mechanism.

The lock cylinder works fine and I have the key. The problem seams to be that I must have disconnected some linkage between the lock cylinder and the release. If anyone has pictures of how this is supposed to work that would be a big help.

John Roncallo

myarmar · #6 10-02-2007, 10:11 PM

...

wscheffer · #7 10-03-2007, 09:46 AM

Quote:

Originally Posted by Roncallo

The lock cylinder works fine and I have the key. The problem seams to be that I must have disconnected some linkage between the lock cylinder and the release.

John Roncallo

You need to remove the lock cylinder (Drill It) in-order to get at the mechanism to trip the lock catch!

The functionality of the cylinder is irrelevant at this point.

Richard Wooldridge · #8 10-04-2007, 12:36 AM

Here's a suggestion that worked on my '75 280...
Remove the license plate, and after looking at another car from inside the trunk to get the location right, drill a hole through the sheetmetal under the plate area large enough so you can get a screwdriver or hooked end tool on the latch arm and operate it to unlock the trunk. After replacing the link, which must have come unhooked, fill the hole with a small piece of sheetmetal or a snap-in plug, put the license plate back on over it, and you should be good to go.

wscheffer · #9 10-04-2007, 05:27 AM

I believe that where you would have to drill is higher than the plate.

Your car not mine...

Roncallo · #10 10-04-2007, 08:02 PM

Quote:

Originally Posted by myarmar

...

Thank You for the pictures that will be a big help. It looks like somehow I must have disconnected rod #8. I now know where to go fishing.

John Roncallo

Roncallo · #11 10-04-2007, 08:07 PM

Quote:

Originally Posted by wscheffer

You need to remove the lock cylinder (Drill It) in-order to get at the mechanism to trip the lock catch!

The functionality of the cylinder is irrelevant at this point.

My thought were that if I had disconnected the control rod going from the lock cylinder to the latch mechanism. Then most likely it was disconnected at the latch mechanism side. I will drill out the lock this weekend since it appears to be the best location and least evasive way to get a fish line ito the trunk. Maybe I will luck out and find the control rod was disconnected at the lock cylinder.

Thank You
John Roncallo

Roncallo · #12 10-06-2007, 08:37 PM

Got it drilled out the cylender with hole saw and was able to actuate the mechanism. No damadge to painted parts. Rod was connected I'm not sure why it dident work.

Thank You
Everyone

rugby2 · #13 04-24-2008, 03:37 PM

the small hole behind license plate was how a shop got my 560sl trunk open. then put a plug in same problem now and I can't duplicate their success with a screw driver. can you describe the hooked end tool? also I am trying to push, not pull(as hook would imply) I have a 2nd 560sl so I have a good idea how far the latch is from the trunk lid, but still no luck. getting ready to drill the tumbler, and put a used one in.

rocky raccoon · #14 04-24-2008, 04:16 PM

Glad you got it open. Back in the day, I used to get into cars rapidly by screwing a slide hammer into the key slot. One slam usually puts the cylinder in your hand.

Richard Wooldridge · #15 04-24-2008, 10:52 PM

I had this problem on my '75 280C, which is setup just like the 380SL. As I recall, I drilled a small hole behind the license plate, and inserted a rod so I could move the vacuum operated trunk pushbutton disable link to the right, so it would be in the path of the pushbutton and actuate the unlocking mechanism. The problem, which I fixed, was that there was an interference fit between the mechanism, the disable link, and the pushbutton. The link has to move all the way to the right so pushing the button actually causes the unlock mechanism to move. I just had to "form" things so the vacuum operated link would move easily into place.