I have a 91 500sl. Saturday the soft top decided not to go down. It is not jammed, the flashing light on the switch functions, there is no release (no noise) of all the locking units.
I unplugged the control module and replugged it in and nothing happens still. The fuses all are good.

Any help??

 

Mine does the same thing whenever I honk the horn. Yeah, really. It keeps blowing a fuse. It may pay to take a closer look at the fuses.

Other things quit working when the fuse blows. Check whether the roll bar, windows, mirrors and other stuff are working okay.

 

No it has nothing to do with the horn fuse. You might be able to stop that by removing the air bag and you will notice the four nuts on the on the back have a rubber sealant on them. The fuse is blowing when the back of the air bag touches the metal in the steering column. I fought with mine for a while to figure it out. It will not blow with the air bag off most likely. When I put electrical tape on any area which might touch when the horn is pushed problem stopped. It is a T27 torx to loosen the air bag if you didnt know it already. Watch your safety precautions when messing with the air bag.

The windows work and the roll bar works. Plus the fusses for the top are in the trunk. The horn fuse is up front.

 

You don't know my car. In addition to what I already said happens, there's a rapid-beeping alarm that goes off when I start the car. The best I can come up with from reading the owner's manual is that the passenger seat back is unlocked, but it isn't. If there's a fuse in the trunk for the top, I've never replaced it, but the top will stop working when I honk the horn and the fuse that blows is under the hood. I'm not saying it's the fuse for the horn. Maybe it is, maybe it isn't. When I replace it, the top and other stuff work again.

 

The first thing I would do is check for diagnsotic codes for the top controller. You'll need a paper clip or wire.

The code retrieval method for the top controller as described here works for cars produced through 12/93. A similar procedure can be used for cars produced from 1/94 through 8/95.

The diagnostics are wired to sockets of the car's main "diagnostic connector", X11/4. These are numbered from 1 to 16. The top control system diagnostic is socket #10.

Codes must be read one at a time. That is, you ask the system to issue a code, you read the code, you ask for another code, and so on. You ask a particular system for a code by electrically shorting the diagnostic socket to ground for 2 to 4 seconds. A second or two after the short is removed, a series of electrical pulses will appear at the socket. The number of pulses corresponds to the number of a code. The ignition must be switched-on for this process.

There are many ways to view the pulses for counting and reading codes. The simplest method is to watch the lamp inside the top switch flash. This is possible because one side of the lamp is wired to the diagnostic socket for the top control system.

Once you have read all of the codes, you may wish to go back and erase them. They are erased individually one at a time. To do this, read a code, wait a few seconds, and then short the diagnostic socket to ground for 6 to 8 seconds.

If you reply with what you found, I can suggest the next step.

 

I will get back to you with the info when I have a little time to test it.
Thank you.

 

I finally took the time to check the codes on the top.
What I got were they all started out with one short flash/one long flash followed by
17,18,19,20,21,22,29 flashes. I repeated this twice and got the same thing.

 

those were engine fault codes.