2007 SL 550
 

I am so tired of these dam luxury cars. My second SL and both abc pumps went out and now issues with the convertible top. It's stuck in half open position. Somebody has to have the solution because Mercedes Benz's techs do not. Also, any help on manually lowering or opening the roof. Mines is stuck

If you press the load assist button and the roof down not drop back into the trunk, then it could be a bad switch on the partition cover.

it seems mercedes is not the only car maker who delivers an overly complex car..
try your owners manual for emergency top issues..
SEARCH this forum for answers..
do a google search for "R231 top stuck issues".. which i did and there are many similar complaints..

top hydraulics in wash state has been my go to source for the leaky cylinders on my R129 and will be when the cylinders on my R230 start leaking..

good luck finding that one thing that has stopped your top from continuing its trip to where you want it..

owners of modern cars had better be more self sufficient than my first car, a 1949 chevy de luxe sedan.. :)

Thanks to this forum. Picked up my SL55 last week and, as I already expected, it had the dreaded trunk hiss.

Took everything apart today, and $5 later, good as new!
As the instructions indicated I was liberal with the epoxy. Including the tabs that hold the diaphragm in place (1 was cracked, the others showed early signs of a crack beginning to form). So hopefully this'll last me a decent time. :)

Hmmmm....
 

I'm a little confused as to why the R230 trunk latch is designed the way it is. It seems the ball bearings must be acting as some sort a check valve. Otherwise, why didnt MB design just cap off the ports to begin with. I understand the cracks that occur lead to vacuum leaks which affect trunk/roof operation but i'm not clear that epoxing the "check valves" to prevent leaks isn't creating another potential problem. What did MB intend with these ball bearings? is there an issue that could be created by blocking them off?

j.Chip

My guess is that these ports as used for access to install internal parts during manufacturing. It's easier/cheaper to pop a ball bearing in there than to use an adhesive to glue on a cap.

Rodney any help you can provide. Looking for a manual way to lower my sl550 2007 top. It's stuck half open

Super explanation for easy close trunk!
 

Your article Really hit the spot. I am having that exact problem and will follow your pics and instructions. If I may suggest... you might consider using a yellow text on your great photos since the red text is hard to read. Not complaining mind you. Just a thought. Thanks again.

Fuse to reset trunk soft close - SEE ATTACHMENT for fuse location
 

Here is the correct fuse to reset the soft trunk close on a 2009 SL550. See attachment

Soft close mechanism air leaks
 

Sorry to continue to hash such an old thread. My '04 SL55 has the same problem and I've followed Neil's excellent epoxy fix but I appear to still have a leak within the mechanism that houses the two electromagnets that control airflow to the two actuators. Specifically, internally it's the down-tube within the first electromagnet closest to the pins for the electrical connection. The bottom of the housing has an outlet and air is escaping there while under pressure. I've checked the O-ring seals and they all look good and there are no cracks or anything that I can see. I've sealed all the "ball-bearing" ports and one hairline crack with epoxy. The behavior is that once hooked back up, the pump will perform soft-close on the trunk, the pump shuts off after a few seconds, then about 10 seconds later the latch pops back open (the actuator in the white housing retracts), and the latch is released. During pressurization I can hear the soft hiss of air escaping.

So... my question is: (before I spring for a complete new unit on Amazon for $285), is this 100% a fault in the latching assembly or could it possibly be the pump in some way? I haven't checked pressure between the pump and the assembly (yellow tube), and the pump seems to operate fine in every other way although my seats functions don't work and I suspect broken pressure tubes there.

Thanks for all the excellent help and advice on these fixes. Love the car - had it about 5 months - but dealership prices make my hair stand on end.

Don in Charlottesville

Update: It's been 2 years since I did the epoxy repair to my trunk latch and it is still going fine, so the method can work well and keep working.

moretech

Perfect results
 

great post, worked but only if trunk is open for short duration
 

Guys, great post, easy repair. I followed the instructions and the latch unit did not look cracked and I did not hear any leaking, but I sealed up the bearing areas with plastic epoxy anyway. I tested it, and still did not hear any leaks. Now it works but only if the trunk is open for less than 30 seconds or so. If it is open longer it does not pull shut that last little bit. Any ideas?

I did not take off the reservoir and seal it, the whole unit look like it was in pretty good shape.

Thanks for the input.

I've already had to make one repair on my trunk latch. The housing for the diaphragm that is used for the open circuit cracked, so I fixed it by clamping it back together with zip ties. When I did that job, I discovered that the plastic arm where the mechanical linkage from the handle attaches was broken. Luckily, I was able to open the trunk lid manually one time! After that, there would have been no way to open the trunk! I drilled two small holes in what was left of the plastic arm and used some bailing wire (twisted and locked in with solder) to reattach the linkage. I really intended to but a new latch ($250) but just never did.

Now, I was experiencing the "usual" leak from the closing mechanism by the ball bearings. The pump keeps running and eventually it shuts off that circuit. So, I decided to take it out and fix it. When I did that, I remembered my bailing wire fix and got a bit nervous about what might happen if the pneumatic open circuit failed again, and my bailing wire fix failed. So, I decided to make myself a little insurance policy. I drilled a hole through the trunk lid so I can access the manual release "just in case". Yeah, I know, I should just spend the $250 and buy a new latch, but what fun is that?

One thing i discovered in making this access port is that the manual release lever on the latch cannot be actuated unless the key is inserted and rotated in the mechanical lock. Basically, the linkage at the handle is "locked" and won't move without the key turned to unlock it. So, if you were to somehow lock your keys in the trunk and need to access it by drilling such a hole int he trunk lid, you would also need to disconnect the metal rod from the plastic lever or else the lever cannot be moved.

I had to drill two holes: one in the metal lid, and another in the plastic trim panel. Found a rubber plug for a 1.25" hole in my spare parts bin (a genuine MBZ part to boot!) so that's the size I drilled in the metal lid. I then drilled a 1.5" hole in the plastic trim panel to access the plug. Here are the pics showing the job. Oh, and after I took the pics, I decided to use some touch-up paint on the white edges of the hole I drilled in the trim panel. It's covered by the license plate, but I wanted it to look decent for the next guy that owns the car.

http://benzbits.com/r230/latch/LatchRepair.jpg

http://benzbits.com/r230/latch/TripLatch.jpg

http://benzbits.com/r230/latch/HolePlugged.jpg

I removed the partiion switch and here is what I saw...
 

Hi,
I have an 06 sl500 and recently fixed the soft close by gluing the ports. Then, after fixing that I get a message to close the trunk and my top won't go down. I then checked to see if the partition was in place it was securely in place. Then I unscrewed the torx screw and investigated the right seat of the partition and




this is what I sawhttps://cimg0.ibsrv.net/gimg/www.mbw...2bf53d3dcb.jpg
https://cimg1.ibsrv.net/gimg/www.mbw...d3840de92e.jpg

THANK YOU 🙏🏽 FOR POSTING THIS
 

You will hear an air "hiss" when opening and closing, but it should last for just a second. If you hear air hissing after the latch actuatres, then there's a leak

This is the best advise EVER!!

Thanks! Followed these instructions, and Voila soft close trunk is back operational, closing on its own. I used a gorilla glue with a Small nail brush to glue the ports. I let sit over night, and then installed. worked as stated, u hear a Hissing sound for a Second then it goes away and trunk is tight. I did have to adjust my trunk Latch a couple times, and I marked it prior to removing. Thanks for the Post

Now Here's a Funny Thing...
 

Good day, everybody. I've recently done the 'seal all the holes in the trunk lock' fix, and it's much better, but it does eventually time out the pump. I can hear the hockey puck leaking air, so I'm going to replace that.

However...

If I lock the car from inside using the dashboard switch, it locks very quickly. If I open the trunk using the switch in the car, it opens very quickly.

If I do it using the key fob buttons, it takes much longer - about twice as long for the doors, and at least three times as long for the trunk lid.:nix:

The only thing I can think of, is that the switch locking doesn't lock/unlock everything, only the doors, but I've no idea why the trunk lid should be different, unless with that, too, the key fob unlocks something else as well. I can't think what, though.

Does anybody have any idea why this happens?

Opening the trunk from the key fob does require the button to be held for two seconds. I think it's a convenience feature so you don;t accidentally open the trunk when grabbing the key.

Thank you to all the members who posted. These instructions are fantastic. I started and finished the fix today and everything went fine. Not hard but a little clumsy nkwith all the fasteners, electrical and vacuum connections. You guys rock!!

Thanks a million. Now I don't have to get out of my car to close the trunk before I put the top down. Woo Hoo!!!

Wooow amazing post thanks
 

This is really one of the most common issues of the SL class
just now I understand why every time I remove the fuse and reinstall it back the trunk soft close works again for some time.
Thanks for this detailed and informative post.
really helpful.
do you have any picture of the gorilla glue we should use to fix it ?? If you have please share it with us.
and I have 2 more questions related to trunk issues if anyone can please help.
1st : my car trunk was standing by itself once I open it now it falls down so I have to keep my hand lifting it.
2nd : how to check and refill the hydraulic oil for the hardtop Convertible roof ( I don't even know where this oil reservoir location ).
* my car is 2006 SL 500 R230 japan imported . Left side steering wheel.
thank you again and hope you all the best