peterkay

Hi,
I am trying to bring back to life a 2003 SL500 that has been in storage for 7 years and many systems are off line. I just solved the issue with the power locks. The fuse for the vacuum pump was burned. I installed a new fuse, which was a bit of challenge because the locks on the rear compartment were also actuated by vacuum, so I had to remove the panel in front based on the search of this forum. Now all my locks are working except for the trunk. The only way I can unlock the trunk lid is by using a small key and then pressing the latch. I see that the key can be removed from two positions in the trunk lid lock. I haven't received the owners manual yet but I tried removing it in both position and the latch still left unloaded and the trunk doesn't open. Nor does it open from the button on the key. At first I suspected a leaky vacuum line but I don't see any lines going to the lid. I think maybe the electronic component is dead? Any advice on how to troubleshoot this>?

PS. I ended up having to replace the pump turbine. The fuse burned again and upon inspection, the fin holder had a small crack that caused a fin to stuck.

peterkay

Ok, the research indicates that the soft close unit maybe leaking air from the puck. I ordered a new one from amazon. Once it arrives I will take it apart and replace it.

peterkay

While I am here, will failed soft close prevent the vario roof from operating? My roof doesn't work either

MikeJ65

Kind of. The roof needs both trunk latches locked in order for the roof to function. You can close it hard enough for this to happen without soft close, but if you close it softly it won't pull in the second latch.

peterkay

Yes, the car was complaining about it but I did close it and nothing new happen. I am kind of stuck with the roof 90% down. Noticed that the oil is low in the pump so will add oil. It is good to know that the two problems are unrelated.

MikeJ65

Try to find your leak first, no need to pump more fluid out.

peterkay

That is a challenge! I've looked everywhere and cannot find it. I think I may have to add some to find where it actually leaks. Do they add flurescent die to this oil? I was thinking about using UV flighlight.

Beeza

Hey Peter, reading through your posts it sounds like you and I are in similar situations. I'm also rescuing a 03 SL500. Same problems. Knackered central locking and a non functioning roof. Trouble is, my car has been in the hands of several really bad mechanics. My main saviour has been getting myself a decent diagnostic reader. I have MBstar with a multiplexer adapter running the software on an old Panasonic tough book. A kind fellow member on here helped me getting all the software up and running. I purchased the hardware off Aliexpress.

Beeza

By the way, there is a very good sticky thread at the top of this section with a good video and explanation on how to repair the leaky boot lock actuator. Mine is leaking as well. Although I did break off the barb that connects the yellow hose to the actuator. Hopefully someone can post the past number of that connector.

peterkay

I suppose all great minds think alike. My diagnostic system should arrive saturday. Yes, my car came as a basket case, but at least it was from the deferred maintenance/storage rather than shoddy mechanical work ( which is getting from me). I am getting one system up and running after another. My PSE issue was due to a pump motor that was stuck. I was able to rebuild in one evening using the new holder and impeller blades. The door locks are functional now. Still waiting for a air bladder to rebuild the trunk lock. Trying to find the hydraulic leak in the roof system in the mean time.

AMGfan2024

I had 3 modules replaced to get the top working , now the trunk power button for the soft self closing is not working from the Trunk nor on the key fob, I have to use the trunk release button on the driver side door!
Anyone else has had this issue?

peterkay

I've done with mine. It leaked from the accumulator. After the new accumulator was put on it was working a short while and then started to leak from the plastic end. I epoxied every end that had a ball bearing in it and it is finally working.

AMGfan2024

Thanks for the feedback, beautiful cars but troublesome when people don't maintain them well !

MikeJ65

I think you are talking about remote trunk closing. I'm assuming that one of the modules you replaced was the RVC module. Remote closing was optional and needs to be coded on the RVC module.

AMGfan2024

Thanks for your reply Mike, does it require a special scanner and if yes would it be easy process or you recommend have a pro do it?

MikeJ65

The Mercedes specific aftermarket scanners usually follow DAS as far as the control unit adaptations. It is a simple change, just a drop down list that has 'Equipped' and 'Not Equipped' or something like that.

peterkay

My view on this car is that it is not the faint of heart people. It is not a car I would own if I had to take it to a shop for every repair. Fortunatly, it is probably the last generation of the MB cars where amateurs like myself can still do repairs such as replacing top hydraulic cylinders. I can purchase used working cylinders for about $100 each on ebay or get a whole lot rebuilt for $12-1500 vs. Paying $1000 to a shop to replace one