Well, I'm in a bit of a quandry with my friend's 1994 W124 Cabrio that I'm working on. It developed a leak in one of the fifth-bow cylinders so I removed both, along with the main top cylinders (which, as near as I could tell, need to be removed to access the 5th-bow cylinders) for rebuilding. As luck would have it, we shipped the four of them to Dennis Ficken the day he went on vacation for a couple of weeks. Needing the garage for other projects, I manually walked the top into place, the system obligingly locked down the rear of the top and the tonneau, and the car was weathertight for outdoor storage until Dennis got to the cylinders.

So here's the quandry: the system is being very uncooperative going in the other direction and will not release the rear of the 5th bow or tonneau. It's no surprise that it isn't being very cooperative given that the 5th bow cylinders are still disconnected and uninstalled (I temporarily connected the hydraulic lines to the main cylinders w/o installing them as fluid was spewing from the lines) along with the electrical limit switch (??) attached to the RH bow cylinder. When the switch is actuated, the rear quarter windows retreat an inch or so and the pull-down/locking mechanism for the tonneau and fifth bow gives a brief, downward tug before it faults and stops trying to do anything. The question: is there a way to access the lock mechanisms to release them, either mechanically or or by supplying current to actuate? They appear to reside in the vault-like area between the rear of the passenger compartment and the front of the trunk. Doesn't look like a brute-force situation (what ever really is?). An additional factor to mention is that in the process of removing the cylinders, I unbolted the entire top stack to gain sufficient access to loosen one of the miserable torx fasteners. While I was pretty careful realigning it, I'm concerned that maybe misalignment is causing the issue and jamming the lock mechanism from releasing. That may just be the paranoia of ignorance as to how the whole thing works. Most likely the process is shutting down before the latches are electrically released. At this point, I'm all ears. If anyone thinks this might get more action on the SL board, I'll repost there as well. I know a few guys here know these things pretty well but searching didn't come up with any relevant posts.

As always, thanks in advance :-)

Did you read the fault codes for the cabriolet mechanism?

I'm not sure what you're trying to accomplish. And am I to understand that you are trying to operate the top while some of the components are missing? It also sounds like you manually got the top up and fully latched. You should leave it that way until the top mechanism is completely repaired.

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95 E320 Cabriolet, 159K

"until the top mechanism is completely repaired".

What you say is true and it's exactly what I did. I left it up until it could be repaired. But, as you know, it can't be be repaired w/o lowering it, can it? So here I am, trying to figure out how to get it down so I can reinstall the cylinders.

Okay, it's more clear now. Basically, you got the rear bow latched during the interim and now need it unlatched. Not having the rear bow unlatch is every cabriolet owner's nightmare. I wish I could be more helpful.

I can't remember exactly, but I believe I replaced the main four cylinders with the top up.

manually unlocking the top and tonneau? It sounds like the R129 Roadster and the W140 Cab's have a Spanner/Allen combo tool and access points for just this contingency. I spent another hour looking at this tonight and see nothing new except that I don't think it's possible to install the bow cylinders w/o being able to raise the tonneau and fifth bow. The mains would not be a problem.

but I can't find the 4-socket connector for the code reader that is supposedly in the front passenger footwell. Anyone have a good description or photo of it's location? I've removed every cover that is easily removed in the footwell and see nothing.

I'm still having trouble getting this thing back together after servicing the main and tonneau cylinders. The roll-over bar will not stay retracted preventing the top from operating. No codes on the roll-over system (that system's socket is conveniently located in the sixteen port diagnostic socket in the engine compartment) but I suspect a top system code may be interfering with the roll-over operation.

The 4-socket connector is under the front passenger footwell below the dash. Lift up the floor mat, the carpet, and remove the metal shield to access the 4-socket connector. The + lead of the code reader goes into the #2 position.

The top will not work unless the roll bar is completely retracted. I learned this the hard way when the fuse blew on my unit when the rollbar was nearly all the way down. It only appeared completely retracted!

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95 E320 Cabriolet, 159K

I have a 1993 300ce cabriolet and the rear bow top is latched after reinstalling the bow lock and I can't unlock it. I am unfamiliar with the code reading process. I need to open the tonneau cover and finish reintall the cover and the 10 srews. Should I take it to a mechanic or do I cut the latch?
Any suggestions?

What you did us something you should never do when working on the top, iirc it's even stated in the fsm. The tonnue lock can be unlocked by the wrench include in the tool kit but the one inside the tonnue for the bow is incredibly difficult to lock.

I think you might be able to access into that area through the small hole for the tonnue lock but having never had to deal with this so I can't really help

Installing the main lift rams is Cake. I used a long flex head ratchet to do it. Didnt ru Ito any issues after all were back in

Thanks ,I will try to work at it. Other wise its cut the latch or take to mechanic.

Is the soft top switch solid red when you try and unlock it? The controller will send the signal to unlock that switch when it thinks the top is up and ready to be retracted. That lock is the first one to be triggered. If your switch blinks when you pull it back you have a fault code, try disconnecting the battery for an hour if you don't know how to clear it.

The tonneau cover lock can be opened manually with the wrench in your tool kit, if you don't have it I believe it is a 10 mm open wrench, bike shop may have it, needs to be thin to fit.

I was able to unlock the top : 1. Remove trim ring at base of of inner back window, 2. used 11mm wrench to unfasten screws on plate which holds latch. 3. Removed latch from lock
reinstallation is troublesome as I had to distort the covering on the plate but I did reattach it ,although I doesn't look factory spec no one can see it. I replaced the trim piece so only the car and I know it was disturbed.
Now I am able to open the tonneau cover and store the top in the compartment.
Next on the agenda is disconnecting the battery for an hour and see if this clears the fault codes. If not ,then off to my indie.
Thanks

I took the car to my indie. He is looking at the top and states he is trying get the switches to communicate. I am waiting patiently for the verdict. Lets keep the fingers crossed.

Mechanic had trouble getting the lower right piston 124800072 -$900 part - 9/13/12 he got it and it leaked- he had to get another piston. I went to pick the car up on 9/16/12-car would not start -he stated it ran fine but he claimed there were month old stored codes re: throttle body issues. While waiting for him to figure out what to do I tried the top .It worked fine going down. But would not close fully. Latch directly behind roll bar leaked.
Mechanic still has car to get it right. Keeping fingers crossed.

You do know that the cylinders can be rebuilt. Look here FAQ | Top Hydraulics, Inc. - Top Hydraulics, Inc and search the forumsfor Dennis Ficken, he rebuilds them.