Hi all,

I have a 1995 R129 with a few roof issues...

Some background:

The main lift cylinders started leaking so I got them both rebuilt by TopHydraulics. The roof was down when they failed so I had to manually raise the roof and make sure the rear latch was ready to receive the soft top to get it locked down properly, this involved messing with the soft top tool and a screwdriver. I then left the roof like that for a while until I received the main lift cylinders back.

Once they were back I added fresh fluid and got installed and got the roof operating going down at first but not up. I manually closed the roof a few times, reset the battery and then figured out if I closed the doors and opened them again then the soft top would close too (read pre-existing condition 1. below - I think it's related).

1. Pre-existing condition: The soft top would only operate up and down completely if both driver and passenger doors were open
2. New condition: I can put the soft top down as normal, but to raise it again I have to close the door and open it again.
3. New condition: The rear left latch keeps trying to secure itself over and over even though it is perfectly secure if I let go of the button at the right time. The button will stay lit and flash when driving, I saw that there are two micro switches for the rear left latch, both seem to have a positive click and when testing with a multimeter showed continuity between the top two pins on the connector as well as the bottom two when the microswitches operate (One needs to be depressed the other shows continuity when not depressed). When the soft top is secured in the latch I have continuity for both microswitches is this correct? I did have to close the roof manually when the main lift cylinders stopped working so my initial thoughts were something has broken with the latch but it seems to perfectly secure the roof as mentioned, it just seems like the controller is not recognising that.



I believe it is either the microswitches for the rear left latch (tested), wiring or the controller. I'm unsure how I can test these so any help would be appreciated.


Video of the roof being closed: https://photos.app.*******/JY5q2HeRuWjdbA3s7


Any help would be appreciated, thanks in advance.

This thread has instructions for checking the functionality of the various limit switches: https://www.benzworld.org/threads/te.../#post14710874.

It's peculiar to me that the doors would have any effect on the operation of the roof, since as far as I can tell they share no common electrical circuits.

The link to our video does not work for me.

Thanks for the link.

Klaus at TopHydraulics sent me this

That fixed any of the new issues mentioned i.e. reattempting to latch constantly and the light staying on.

So I am now back to the pre-existing condition of the doors having to be open for the soft top to work. Klaus also mentioned:


Some more things to note:

• I checked all the fuses and it looks like it is missing fuse in position 5 in the boot for a reason as the horn will constantly go off if I put a fuse in which suggests the alarm has been disabled? The car has an aftermarket Sigma alarm installed.
• The car has an aftermarket stereo, I read somewhere that the speed signal to the radio can mess with the controller (? - unsure about this one)
• I can open and close the roof while the car is moving (doors still have to be open)
• I have always suspected that my windows should drop when the door is opened as some of the rubber around the edge of the window doesn't look right, neither of my windows drop at the moment. I have already tried to search for the switch in the bottom of the door but found nothing, I believe I have the hall sensor type of window regulators. When I open the roof the windows drop all the way down, when I raise the roof they stop about an inch short of closing.

Hopefully, someone can help with some testing procedures with the windows dropping, I also want to try the led diagnostic reader but suspect it won't show anything.

Cars made from December 1994 and later have the window drop-down feature.

A green wire with a black stripe went from the instrument cluster to the original radio, and it carries a vehicle speed signal. I presume this wire is now connected to nothing, and it apparently is having no effect.

I would see what changes electrically at the roof controller's electrical connectors when you open and close the doors. If you provide more detail on what happens or doesn't happen when you operate the roof with the doors closed, then I may have further guidance.

Thanks, I will get my multimeter out and have a look.

When opening the roof it will open the rear cover, lift the rear part of the roof and then start lifting the front. The front part of the roof will go almost vertical and then it will stop. Once I open the doors i.e. literally pull the door handles but keep door almost closed on the first part of the latch the roof will start moving again and complete the process.

When closing the roof it will start to close and get to the same position as above and it will stop unless again the door is open.

I will have to get a picture of where in the process it is stopping. I was going to try and keep the door closed but just operate the door handle to see if it worked.

Is there anything that would stop both windows dropping together, it seems odd that neither work.

If your car was manufactured in or before November, 1994, then you have a limit switch in the bottom-center of each door. If those switches are falsely signaling the windows are lowered, then they will not move. But I don't think this is your problem...