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How to unlock your boot/trunk without keys - a guide

Started by SteveDuNord, 12 January 2024, 08:14 AM

SteveDuNord

* Apparently you can access the same hoses (more or less) under the hood so just do that! *

Having previously locked my keys in the car I have now managed to lock them in the boot  ::)

Thought I'd show some pics of how I got it open, thanks to previous advice given on here.

To start, push the right hand side seat forwards and remove the b pillar plastic trim that holds the seat belt, it's just two screws at the base, v simple.

Next, pull back the carpet and you'll see some fibreboard that is glued on, below that is a plastic trim that you need to remove.

Here's a pic of the b pillar trim removed and the fibreboard, the plastic trim below.




For the plastic trim - just a couple of grommets  located towards the rear bench seat. I used a trim tool. A cap and pin comes out first, then the anchor separately.



Pull away that trim until you see some vacuum hoses in a rubber T fitting.




Focus on the yellow/green and yellow/red hoses going in the direction of the boot/trunk. You now need to remove one from the rubber T and either apply air pressure or suction depending on which hose you are using, the green one is suction and the red is pressure (blowing air down it). Both will work to open the boot!

I pulled out the yellow/red hose and used an oil suction syringe in reverse to blow air down. Had to use my fingers to close off any air escaping from the syringe/hose connection but if yours doesn't fit tightly, consider some tape or heat shrink. You could also use a bicycle pump or whatever.

Took a few goes but eventually it popped open.  ;D



Hopefully I didn't damage the diaphragm.



'77 280se

revilla

The old fashion way, it never fails.
You could have used, for simplicity, the yellow tube/hose entering next to the fusebox as you had access inside the car and the driver's door lock.
Pulling vacuum from the yellow one, driver's door unlocked, would have unlocked your trunk/boot too, providing there are no major leaks in the system. The reverse is also true; pumping air through the yellow one driver's door in the locked position would have made the trick.
The preferred method is pulling vacuum to avoid damaging the diaphragms though, as you said.

SteveDuNord

Quote from: revilla on 12 January 2024, 01:43 PMThe old fashion way, it never fails.
You could have used, for simplicity, the yellow tube/hose entering next to the fusebox as you had access inside the car and the driver's door lock.
Pulling vacuum from the yellow one, driver's door unlocked, would have unlocked your trunk/boot too, providing there are no major leaks in the system. The reverse is also true; pumping air through the yellow one driver's door in the locked position would have made the trick.
The preferred method is pulling vacuum to avoid damaging the diaphragms though, as you said.

Now you tell me!

There must be a reason for previous advice leading me towards doing it the hard way, maybe because it's closer to the boot?
'77 280se

revilla

Of course there's a reason Steve, actually 2 solid reasons. Distance to the trunk is irrelevant. Perhaps you read that advice in a case where there was a broken diaphragm in the middle (?).
There are specific cases (with specific advice) where people leave the key in the trunk but the car is locked with no access to its inside but hood opened/accesible.
Also, there's a check valve hidden in the dashboard between that fusebox point and the air switch in the driver's door that wouldn't let you just apply positive pressure (pump) through that yellow tube to unlock the car. That little thing was placed there to avoid the bad guys from simply popping up the hood, connecting a cheap bicycle pump at that point and unlocking the whole car. You can argue that the bad guys could just simply break a window to gain access and steal things in the insides, true.
It's common occurrence that the air switch fails, or that there are broken diaphragms in the circuit on the way to the trunk. When that's the case, the solution you applied is the best (only?) choice.
My point being, every scenario is different and every case requires a specific set of solutions. Your circumstances were such that there was another (simpler) solution, that's it.
But it all comes back to the point I always make here, the key on these cars is first understanding how the problematic system works before applying generic solutions that might (or might not) work. How many times you hear/read things like "change such part, that will solve your problem" and the owner coming back stating that did nothing to solve the problem after spending €€€...
Anyway, I think I remember you. You had mixture related issues some years back and we tried to help you start your engine. I'm guessing you managed to pass that stage and engine's running smooth/well and you moved to another item in the list leaving the key in the trunk in the process. That happens to all Steve. It happened to me many moons ago when I started working on W116s. Visiting family 2 hours from Paris I accidentally left the key in the trunk. Tried many things. Luckily I, despite temptation, didn't break/drill anything. Embarrassed, borrowed another car, went to Paris, recovered the secondary key and came back. But that's ok now, I'm the one fixing family cars these days in my free time, so that bad episode is officially behind (yet not forgotten it still comes up from time to time during Xmas dinners :) ).
Cheers
Robert


SteveDuNord

Yes one fella had diaphragm issues but another simply had a broken boot lock, and I'm guessing somebody directed him to the diaphragm guy's solution to opening the boot?

As far as my other problems - car has barely run since I bought it. No solution. I'm aiming to get it back on the road this year.  :-*
'77 280se