Is it possilbe to open the trunk, clk320, from inside the trunk when all other attempts to unlock it fail?

If there was it would be right by the trunk latch, but usually it has a wire with a bright yellow pastic tag so you can't miss it. It's a emergency release if you were to get locked in. Sorry, but I don't think this feature was available in 1999. I'm surprized you dont have a button on the dash near the fuel door release button or in the glove box, both of which were common back then.

I do have a button in the console, It also does not work. So How do I get this bloody thing open with out the emergency release from inside?

I heard somewhere that under the carpet in the truck there is a pump that activates the trunk release via the FOB & if you clean it, by blowing compressed air on it the FOB might work. But IDK, its strange that your key wont work either.

Did you ever figure it out? I am having the same problem. The key and the trunk button neither are opening the trunk. I dropped my keys a few months ago and a few days later the key wouldn't open the door. I had the battery replaced but it became increasingly harder to open. Now the battery is run down and I can't get into the trunk to jump it? Any help will be very appreciated!!

Hard to say. I was able to get the trunk open and have never had the problem again. What I did was pure luck. I had the rear seat fold down disengaged from carrying something long. As I never relocked it I was able to access the trunk from the back seat. Once in the trunk I was able to manually trip the solenoid that holds the trunk lid closed with a screwdriver. Unfortunately the release for the seats is also in the trunk so if they are not already released you are out of luck. I keep one side permanently unlocked now just in case. Good luck. Seems like Mercedes needs to put in some sort of override somewhere.

I have the same problem. Despite applying power from another battery to the jump point under the bonnet, the boot realse button wont work and the key wont either. Luckily the drivers side rear seat is unlocked but I cant get right into the boot. Can I trip the solenoid through here and if so what am I looking for?

I just encountered the same problem we think bat dead or needed reset computer

I have a 99 Clk 320 coupe which has the metal key inside the normal key and what i learned is, take the metal key out put it in the trunk do not push it but turn it to the left and leave it there and then push the button in and it should pop open. My car has no power at all at the moment and it worked for me!

P.S..take it from me..there is no trunk latch inside the trunk. I learned that by experience! :)

You can unbolt the body part of the latch from inside the trunk. There's a 1" x 2" plastic cover just below the latch. Prying this cover open reveals two bolts. Undo the bolts, trunk springs open.