[dbischoff]

I have a dilemma here. My 2010 SL63 is in my garage with the top down. The top won't go up and it is rainy, so I'm unsure of how I can get to a dealer.

I suspect the problem might originate with the notorious leaky trunk "soft-close" actuator. First symptom I noticed was the pump coming on more and for longer when I start the car. Then I noticed when I put the trunk lid down it would slam instead of doing the soft close. This went on for a while, then the other day I discovered that the trunk lid would not go up on its own. I had to forcefully pull it up, and the lowered top inside the trunk would not tilt up to give access to the storage space. The trunk lid would close normally (other than the slam) when I pressed the button to close it. Then I realized I couldn't put the top up either. I can hear a relay in the fuse panel behind the passenger seat, but nothing else, and that pump isn't going on. The trunk battery is fully charged.

The related threads I have read refer to a circuit that will disable itself because of an air leak, and can be reset temporarily by pulling a fuse. However, different instructions seem to point to different fuses. I tried pulling quite a few of them, but no luck. Either I'm not getting the right one, or I'm not waiting long enough, or the cause of the problem is something else.

I'm just hoping to get the top up so I can investigate further to DIY or get it to a dealer.

This is a lightly used, pampered car with no wear and tear - about 25,000km (16,000 miles), always garaged at home and never winter driven.

 

[Zephyr411]

I don’t know if the roof system is different than the earlier R230 body style that I have. If it’s substantially similar (hydraulic), I would suspect a leak in one of the hydraulic cylinders or possibly the PSE pump if the pneumatics aren’t functioning either.

Does the car lock and unlock? If not, it could be the PSE pump (or related) since that affect the hydraulic pump. My PSE pump failed a couple of years ago and I think that was one of the obvious symptoms besides the roof not working (which wasn’t at all obvious to me that the PSE pump was the source...)

Also, are you able to check the hydraulic fluid level in the reservoir in the trunk?

If it’s low/empty then you are probably losing fluid through one of the roof hydraulic cylinders. In a pinch, you can top it off to close the roof, but, of course, the new fluid will leak out wherever the faulty seal is...

Failing that, there are YouTube videos that show you how to manually close the roof (and you can find instructions on this forum also)

Hope this helps!

 

[bobterry99]

The pneumatic function of the PSE pump is non-essential to the operation of the roof. The pump's only role is to monitor the status of the trunk partition.

I wouldn't bother to try to troubleshoot a roof problem like this without Star Diagnosis.

 

[rudeney]

If the pneumatic section of the trunk latch is leaking, the PSE pump will shut down to prevent it from burning out. When that happens, the mechanical part of the latch will still function and the trunk will appear to be closed, but it won't completely pull down tight. If it is not fully closed tight, the vario roof will not operate. You may be able to get the pump to operate by momentarily pulling its fuse to reset it. It might then work once to get the latch pull down so that you can close the roof.

On your car, this should be fuse 54 on the rear panel (under the storage compartment behind the passenger seat):

https://benzbits.com/R230/fuses/RearFuses/MY2009_MY2012_RearFuses.pdf

 

[dbischoff]

Thank you. I think I tried every fuse but that one. I couldn't make sense of the fuse chart I had. If it works and resets, then perhaps I was on the right track to suspect a leaky trunk latch, which, from the info I have found, looks simple to patch with epoxy or just replace.

If the pneumatic section of the trunk latch is leaking, the PSE pump will shut down to prevent it from burning out. When that happens, the mechanical part of the latch will still function and the trunk will appear to be closed, but it won't completely pull down tight. If it is not fully closed tight, the vario roof will not operate. You may be able to get the pump to operate by momentarily pulling its fuse to reset it. It might then work once to get the latch pull down so that you can close the roof.

On your car, this should be fuse 54 on the rear panel (under the storage compartment behind the passenger seat):

https://benzbits.com/R230/fuses/RearFuses/MY2009_MY2012_RearFuses.pdf

 

[rudeney]

Here is a set of fuse charts:

Benzbits: R230 Fuses and Relays

The fuse in question is on the rear panel, so drilling dow for your model year:

https://benzbits.com/R230/Fuses/RearFuses/MY2009_MY2012_RearFuses.pdf

It's 54.

 

[Kona Jack]

similar but different problem. top down, but trunk won't go all the way down at cockpit side ....front...edge. now nothing responds, can't open trunk with key to access anything. flaps appear flush. fuses all good. vacuum things still work. how can i get the trunk open from that position to get at the pump

 

[rudeney]

Make sure you know how to use the blade key. You have to turn it AND pull the handle (this shows a CLK, but the SL is the same):

 

[Kona Jack]

of course.....i used the key many times when i was solving my close assist problem. found that this is not an unusual problem, and some have been able to wriggle it open. not this one. handle feels as though it is meeting no resistance.../..key does feel like it is doing what it should. found a guy getting worked through on just answer, but they went to phone before the solution. claimed it was solved. thinking about getting star since this beautiful little buggy appears to be a can of worms. have a feeling the pump went tits up in mid process. had a good feel of the pump when i pulled the pse.....did not check the level, but it was pretty dry outside, and had what looked like enough in the reservoir. had it only less than two weeks when the abc blew with quite a loud bang....then the close assist, and now this. for every day i have gotten to drive it,,.....it's been on jacks for 10. buyer's remorse.

 

[rudeney]

Your latch might be broken. There is a plastic lever that is actuated by the handle when manually opening the trunk and it can break. Mine was broken, and I discovered it when I removed the latch for the pneumatic repair. You can see my repair in the 1st photo below. When you turn the key, it engages a pawl inside the handle that allows it to engage the metal linkage rod. When you then squeeze the handle, the rod pulls up on a plastic lever in the latch that releases it. The metal rod snaps into the plastic lever. On mine, that plastic was broken so the the rod was detached. I tied the end of the rod to the plastic lever with bailign wire, and then I soldered the wire so it could not twist loose. This fixed it, but just in case, I drilled a hole in the trunk lid (2nd photo) and put a plastic plug in it. If needed, I can remove the tag and the plug and use a screwdriver to trip the latch.

 

[Kona Jack]

it was less than two weeks ago that i had that out of the car for the epoxy job, and it was all solid. continued to work fine until the top jammed. i'm going to see if i can reach any hydraulic hose fittings through my small gap, and with a lots of rags....detach a line to relieve pressure so the lid can be moved manually to full reverse open. have not looked yet..was one of those middle of the night thoughts.

 

[rudeney]

Hmm, unless the latch is broken, the way the manual latch release works, the trunk should ALWAYS open, in any position.