floridabrits

Excellent post. I am a bit worried about messing it up - is it really as easy as it looks?

Do you glue the ball bearings in place so they won't move?

What glue do you recommend for best results?

Finally, if I can't fix it, do you know what part I should buy to replace it (part number and description)?

I have a 2003 SL500 that has this problem and removing fuse 71 fixes it for about 2 days only, so am guessing it's the leak issue ...

Thanks again for the excellent post and look forward to hearing back on my questions?

Cheers!

pleeson

I used a 2 part epoxy, worked well.
Ball bearings are wedged in and can't move.
Don't worry, you'll fix it!

floridabrits

Thank you! What brand of glue do you recommend? I have purchased Loctite Epoxy Instant Mix (for metal, wood, ceramic, stone, glass, tile and most plastics) - is this the right type of 2 part epoxy please?

Also - do I actually cover up the ball bearings with a blob of glue?

This will be my first fix job so if I can do it anyone can!! ...but want to be clear that I should cover up the bb's with glue as well as cover up any cracks etc.

I will post back on how easy I felt it was afterward, if someone can just confirm my questions above please....

Thanks again in advance...

floridabrits

Fantastic post guys... I am a total newbie and here is my experience...

- It was really easy to do:-)
- I took my time to make sure I didn't mess anything up and it took me 1.5 hours (you could probably do it in half this time)
- I took pleeson's advice and disconnected both the electrical wires and the yellow air tube so I could remove the unit completely and work on it away from the vehicle
- While I was working on the vehicle, I pulled the 20 amp fuse (71) out and pushed it back in before testing (didn't do any battery disconnects)
- I did not see any cracking or damage at all to my unit - it looked absolutely brand new (I have a 2003 SL500)
- I therefore sealed all 5 of the ball bearings up with Loctite Epoxy Instant Mix... still could hear air leaking...
- Finally figured out the air was leaking from somewhere that I couldn't physically see (but could hear), so just globbed up (technical term!) the area where I could hear the air escaping with a couple of grape sized blobs of glue and firkled (another technical term!) the glue about until it had completely covered up the area (it looked a bit messy, but I cleaned it up a bit as it was drying and in the end it didn't look too hideous)
- I let the epoxy dry for about 25 mins and tested again - the leaking air sound (when simulating closing the trunk) appeared to have disappeared :-)
- I simulated the trunk closing/opening by pushing the locking mechanism latch in and then opening immediately with the tailgate latch opener (repeatedly) rather than physically opening/closing the trunk as I still had the trunk carpet etc. removed and it was in the way
- I had no bits left over :-) and all I needed to complete the job (in addition to the glue) was 2 small plastic cable ties to replace the 2 that were removed

All in all - I would say this is a 10 out of 10 for instructions and a 3 out of 10 for difficulty... excellent! :-)

If you don't see a repost from me in the next month, you can safely assume this resolved my problem ...

Thanks again MBworld - fabulous community/collaboration here - love it :-)

webuycarnotes

I'm brand new to the site, and relatively new to an R230 (2005 SL500), but I have this trunk soft close issue as described.

Will try this fix soon and advise. Thanks to all the folks that spend the time photographing, writing, and posting this fabulous information. What a country!

dis6933

Hi to all
I had a similar problem on my S430 (2002) but my failure was different.
I removed the opening mechanism from the trunk lid and then noticed that
the "black puck", which is a air operated device, had separated into two parts right at the middle. The plastic catches had broken off allowing the separation, and thus the air to escape. I did not notice any air escaping from the so called a ball bearing vents.
I put the puck together again, and wrapped some bailing wire around it in 3 locations at 120 degrees, twisted the wires to create strong binding, and put everything back.
I has now worked for over 30 days, and it saved me over $800.

jrscorpio7

Oil filter housing on 05 SL55 AMG is leaking on bottom. Can anyone send me any pictures or instructions on how to remove/replace the seal ring of the filter housing on a 05 SL55AMG?

CLUBVIEW

I am having a problem from last few weeks my driver side door window won’t sit all the way up about 1" lower so when I start to drive the car it says door is open so I did the usual rest and all but it would fail randomly or one time when everything was fine running hour later the burglar alarm comes on obviously thinking the door is open
I changed the driver side door switch thinking it was the problem
Then I did a test by opening the trunk with remote and immediately the window went in correct position as soon as I pressed trunk shut the window went down...

I think I might have the problem as you described I appreciate your effort to explain that thoroughly .I will tomorrow check what you recommended... the beauty of new technologies...
One more note if I did not drove the car for few days and at first start it will have warning Consumer electronic of line (as the battery is not charged one in the trunk) and there is nothing wrong with the battery
2004 SL500

austinn

Help! I have a latch related problem and wondered if anyone can advise me? I have had my consumer battery on trickle charge for the last week with the boot open and now the latch release on the boot is continuously operating so that as soon as I close it it reopens. Also the trunk release button on the drivers door is illuminated all the time. I had not realised that the red button in the rear is an auto close button but that does not operate either. I have had to disconnect the consumer battery as I was concerned the lock would get damaged by continuously switching. Any suggestions for where I should look first?
Thank you.

Nick

mercedes4ever

Disconnect the main battery; Negative cable first, then positive. Leave it for 10 mins, then re-connect in reverse order. You will have to reset elec windows / sunroof & esp. All should then be fine.

dis6933

I suggest you reconnect the battery and see if the reset by disconnecting stopped the cycling.
You may try to push the green button on the inside of the trunk and determine if this stops the issue. I am not aware of any other resets.

As to the windows, you have to raise them via switch to the topmost position and then hold the switch for a few seconds. It is described in the Manual how to reset all widows, etc.

Note that you can open all the windows with the remote key, as well as close all the windows, but they have to be synched.

austinn

I tried reconnecting after 15m or so but the latch immediately continued operating again. The soft close is also disabled/not working I think.

Mikedealer

Hello All, came across this thread couple days ago, and was wondering if anyone can give me some input on my issue..

My Trunk assist about a month ago was not working as described here, it would work when i disconnected rear battery and reconnected it.. then the trunk would soft assist again no problem.. over a month i had to do it about 3 times..

Now my issue appears to be that My door locks do not work either (which are all vacuum related).. brought it to my local MB dealer, they said it was a fuse that blew and it was all fixed, didnt charge me for time/fuse... but now its happening again today, door locks wont lock and trunk assist is like in the locked mode now...

I read through this post, but still a bit confused if this is the problem with an air leak, or if my central pump went bad somehow? Im going to replace the fuse again now once i find but, but any advice would be really helpful if anyone is knowledgable about this issue

thank you

ken beeler

Here it goes! my auto trunk closer is not working at all. After looking @ discussions about this here some say you should hear the sound of air by the latch . I don't hear a thing there. now for the good news' there is good resistance when i use the hard key and pull the trunk open & close it. also after i open the trunk almost all the way if i hit the remote button the trunk goes up a bump hit it again and it bumps up again until its all the way up . Thinks in advance

DieselMartini

I followed the excellent write up and I have a few things to add.
I took the locking unit out by disconnecting the yellow pressure line. It just snaps out, I used a flat head screwdriver and carefully pry it out. It is meant to be unplugged.

Once I had the unit out, I could see a hairline crack at the end, next to the ball bearing, of the black cylinder that the yellow tube connects to. I also hooked up a MityVac to the opening and it would not hold pressure or vacuum. I epoxied the end of the black tube, and let it cure for about 12 hours.

This is how to test this locking mechanism:

The yellow tube pressurizes the push rod and pushes it out. As you are applying pressure the rod will slowly move out. The rod should stay out as long you have pressure applied. Once pressure is released the rod will move back.

I had a hairline crack at the end of the black cylinder. I epoxied it, using Harbor Freight two part epoxy glue and let it cure for 12 hours. I put everything back together, pulled the fuze out, 20 seconds later I put it back in, and the trunk lid closes smooth as butter.

No other ports were epoxied.

DieselMartini

Also you may find that the white clips holding the trunk lining are broken... So I used these from NAPA. Perfect fit, all you have to do is snap the top off and use some sort of pliers to push into its holder:

drobinson117

Four days ago I had fuse #71 to blow and my trunk lock would not work and none of my door locks would work either. Pulled the trunk mechanism and epoxied the ball bearing sealed ports. On a 24 hour cure now and will post the results tomorrow. Mine is a 2003 SL500. Don't know why the door locks don't work if fuse 71 is the only one that blew. 9,26,38,41, and 57 are good. Will test the system tomorrow with a new fuse in position 71 and see what happens and post the result here.

Twenty fours later....put a new 20 amp fuse in position 71. Heard something like the air motor run, stop, immediately run again and blew the fuse again. Never have heard an air leak. Frustrated!!!

Sicari

Just the other day I had a similar issue as Nick's original problem, where the trunk of my Wife's 2007 SL550 suddenly stopped working. It wouldn't open in the unlock position with the handle or the remote. I had to use the key, turned completely to the left to open the trunk, and after a bit of inspecting I could hear air escaping at the latch mechanism. Here is what I found.
Following Nicks original post I removed the truck latch assembly. During the removal a few small pieces of black plastic (see below) fell out from the trunk carpet liner, which came from the small air actuated plunger. Apparently over time the plastic becomes brittle enough that the small clips that hold together the air actuated (key-less remote) plunger assembly together break, then separate enough to allow for an air leak, consequently (I believe) the pump will time out.





The bad news was I couldn't repair this with any epoxy or glue to satisfy my **** retentive ways, so I opted to buy a replacement unit from my local MB dealer ($317.00). The good news was following Nick's original post, the replacement literally took me 20 minutes.
Nick great post, hope this additional tidbit helps anyone else with a similar problem.

RoundTheBenz

Hi All, I don't have any soft close function but everything else seems to work spot on. I was looking into this fuse 71 before I attempt to locate it but the fuse chart I have (downloaded online) references fuse 71 being used for multiple systems. Maybe I'm reading it wrong?

What about location, is it passenger side in the storage box?

Thanks all.

flittlejr

In my tool kit came a fuse chart, divided into 3 columns for the 3 fuse boxes. scan for fuse in different colums and you will know which fuse box and which fuse. If you don't have proper chart let me know and I will look at mine a give which box and location. Work today but will reply tomorrow if help needed.

DavidCA

Yes, in the bottom of the storage box.
It is fuse 71 (f71) 20amp, yellow.
See the attached photo.
This fuse is solely for the PSE (central locking pump)

Regards

RoundTheBenz

My fuse setup on the 2003 S55 looks a bit different to that. Mine is the 20amp fuse located in the black box with no fuse the other side.

As one of the other guys said, I unplugged the fuse and put it back in and the soft close started to work again for a couple days. It's not working again now. I guess I'll have to try the epoxy fix next...

next2pool

I didn't even know I had a soft close trunk until I read this sticky. I repaired mine just like the instructions and it works perfectly! Thanks for this excellent write-up !

rover75golf

Thanks for the info , really detailed ? not sure if my 2002/03 has the soft close but will check tonight when I get home

Dadunn06

Niklein06,
Followed your directions to the tee. After I did everything, had to reset the trunk battery. And low and behold it worked! Now I just hope the gorilla glue sealed up all the air leaks and the battery reset is not just the temporary fix as I read earlier. Great info. One dealer quoted me 1400 to replace the pump or 500 for the latch, but they mostly said they I would have to bring it in first which obviously is not complimentary. Thanks again for the info!