[rlmcdan36305]

All,
I have a 91 500sl with recently rebuilt cylinders. I lifted the top into the fully up position, did the sync process, everything locks into place. Even the top button goes off and appears normal. When trying to lower the top, things start fine-windows lower, things unlock, but the bow never lifts out of the way of the toneau cover. If I manually lift the bow to the up position and then return to lowering the top, all goes as designed. When trying to close, windows go down, toneau cover unlocks and lifts up.then the top starts to lift, but lifts maybe a third of the way up then goes back down. If I hold the button the top will go up and down in this part of the cycle, never proceding further in the process.
I cant see any leaks from any cylinders or lines. With top up or fully down, the top button no longer glows.
Any ideas on whats causing the odd behaviors or how to fix is greatly appreciated

 

[mrelbe]

Sounds like the cylinders that operate the bow are not working.

 

[Lighthouse]

Top stopping in the middle of the cycle - hydraulic lines mixed up, or micro switch?

rlmcdan36305,

Thanks for the detailed description.

You could have a malfunction in the micro switch on the left bow extension cylinder, or it is possible that the lines to the bow extension cylinders got mixed up and the cylinders are working against each other.

The numbers stamped on the side of the bow extension cylinders match the red numbers stamped on the hydraulic lines.
Right Bow Extension Cylinder: #85 on top and # 94 on the bottom.
Left Bow Extension Cylinder: #87 on top and #96 on the bottom.

If the switch already signaled to the controller that the rear of the bow is up before it actually happened, then the controller would move on to the next step without raising the rear of the bow.

Two ways to test the switch now:

One, disconnect it where it plugs into the wiring harness (behind the door). That signals to the controller that the rear bow is not fully up yet. If the bow now moves up during the opening cycle, then you know the switch gave the wrong signal.

Two, when the top is up, move the rear of the bow and listen for a click from the switch. That is not conclusive, but you might learn something.

Window synchronization is only needed on model years '95 and up, by the way (the ones where the windows drop a little when you open and close the doors).

Hope this helps, and please let us know what you find,

-Klaus

[email protected]

 

[rlmcdan36305]

Klaus,
I can in fact hear the micro switch clicking-when the bow is at 85degrees and moving to 90degrees(full vertical).
If I unplug the ms connector, I get NO movement from the bow, or the toneau cover.
I wiped both bow cylinders carefully with a dry cloth and let sit overnight. I still didn't see any leakage
I am at a loss logically on this one....Thanks again for all help.

 

[Lighthouse]

How about the rear locks?

rlmcdan36305,

normally, the next step would be to read error codes in the controller, which is well described in the RST Controller Ultimate Thread http://www.benzworld.org/forums/r12...ft-top-electrical-controller.html#post2419223.

One more thing comes to mind, though, for you to check if you wish. It is possible that one of the rear locks is not indicating open position, which would prevent the controller from going to the next step of raising the rear bow. This is quite unusual, because the rear lock micro switches are pretty reliable in their readout. However, I recall now that one of your rear lock cylinders had been "worked on" by the previous owner, and we had to work pretty hard on buffing out the damage he caused (scratches on the shaft). Maybe the same person also felt that they had to mess with the wiring or switches on that rear lock...

Please let us know what you find,

-Klaus

[email protected]

 

[rlmcdan36305]

One thing I noticed last night, oneau cover is trying to lift even tho the bow has unlocked and lifted a few inches only.

 

[rlmcdan36305]

All,
So I ran the top code procedure (shorting pins 1 and 10) and got two quick flashes then nothing from the top control button. I was unable to erase this code.
As I see it, code 2 would be
Limit switch, left locked soft top cover

What exactly does this mean? Is left driver or passenger side?
How should I proceed?
I also noticed that after I remove the key and open the drivers door, I get 5 chimes.
Is this indicative of anything?
Thanks again for your help!
R

 

[Lighthouse]

code 2

rlmcdan36305,

this code means that there is a troublesome signal being read from a micro switch on the left tonneau cover lock. That's rare. If this is the only error code, there is either a malfunction around a micro switch, or there's a wiring problem.

I would take the brass cover off the left (driver side) lock and see what's going on with the micro switches: open and close the lock manually with the soft top tool (ignition off). In order to close the lock manually without the tonneau cover being pulled down in it, you have to push down on the lock a little before the soft top tool can turn the lock (simulating the cover's prong first pushing on the lock so that it can be pulled down...). Study if both limit switches are being pushed or released as the lock goes through its cycle, or what might be preventing the proper function. Can you hear the switches clicking? There is normally no need to adjust the switches.

Please let us know what you find...

-Klaus

[email protected]

 

[rlmcdan36305]

So,
The micro switches appear to be tripping correctly. I can even hear the switch clicking as its actuated. I havent retried checking the codes, tho, as the top behavior is still the sane. I re seated the connections on the lock at the plug. With top up or down fully the top switch now doesnt stay on and the only chimes are after I remove key and open drivers door (5 chimes). I did notice that during the last closing cycle the drivers door window stopped halfway up and I couldnt continue to raise the window until I opened and reclosed the door...
Is this an indicator of the dread soft top controller? Is there a better test for that?
Also, I noticed the passenger bow cylinder appears to be weeping some...guess its that joy now..

 

[Lighthouse]

coincidence?

Rlmcdan36305,

The details you are describing are frustrating. I would tackle the following at this point:

- Disconnect the negative battery pole over night to see if any of the parts that don't make sense in the controller behaviour disappear

- Check whether the electrical signal indicating "tonneau cover unlocked" ever makes it to the controller: first at the connector on the lock, then at the Y-connector at the controller.

- If the window problem persists, check whether the limit switch in the driver door is giving you a false "window closed" signal. Or is the window going up with the window switch when the soft top cycle only lifts it part way?

-Klaus

[email protected]

 

[rlmcdan36305]

So....disconnecting the battery did seem to clear up my window issue, but only that one.
I checked the tonneau cover microswitch at the plug at the switch and they are working.
Where is the Y connector? any idea where I might find a schematic to know which wires to check?
As far as top operation, I did notice that after the bow unlocks and lifts slightly there is a slight pause and then the cover unlocks and tries to lift, obviously unsuccessfully. If I disconnect he bow switch(which I can hear clicking slightly as I move the bow up and down- notably from 85 degrees thru 90 degrees) I get no action at all when trying to cycle the top.
Is there an adjustment on the bow ms?
Any input is appreciated.

 

[Lighthouse]

progress

So....disconnecting the battery did seem to clear up my window issue, but only that one.

Good - that's progress!

I checked the tonneau cover microswitch at the plug at the switch and they are working.
Where is the Y connector? any idea where I might find a schematic to know which wires to check?

Here is a quote from bobterry99:
"When a switch closes to signal the controller, it does so by completing a circuit from the controller to chassis ground. All of the switches are wired to the Y connector of the soft top controller. You'll need a basic multimeter or other device for measuring continuity between the inputs and ground.

To access, open the storage compartment behind the passenger seat. Remove the plastic cover that protects the soft top controller by loosening three 10mm plastic nuts. Now remove the two 10mm nuts that are securing the controller and lift it off of its mounting studs. Now you should be able to easily separate the Y connector from the controller.

Looking at the connector you will see two rows of sockets numbered sequentially. Nearly all of these are inputs from the switches, though some are not used. You proceed by putting the top in "Position 1" and checking all the switches and then repeating the same for "Position 2". The info below shows which inputs should be open and which should be closed for each position. Have the ignition off while you perform your checks. Note that you only need to check 17 inputs.

Position 1 (Top closed, windows up, roll bar up)
Open: 10, 22, 27, 29, 30, 31
Closed: 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 28

Position 2 (Top open but storage compartment cover open, windows and roll bar down)
Open: 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 28
Closed: 10, 22, 27, 29, 30, 31"

Without consulting WIS now (I'm short of time tonight), I don't know which ones are the tonneau lock micro switches, but you should be able to figure that out by wiggling the micro switches when measuring on the Y connector.

Is there an adjustment on the bow ms?

Not needed. Your test confirmed that the switch is working.

-Klaus

[email protected]

 

[rlmcdan36305]

Well, It appears all my cylinders are now dry and functional. However I guess its time to look at the module as mt top is still doing the wierd bouncing when trying to lower and nothing after the toneau cover unlocks and the rear bow lifts about 2 inches...
Klaus, for this testing do I need the rear interior pieces off or is should I go ahead and reassemble the jump seat panels since the cylinders are bone dry now (thankyou sir)?
I still get code 2 (2 flashes only) when testing. I can clear it but it comes back. I can hear each tonneau cover lock lock into place and unlock so Im guessing its a controller, wiring, or switch issue. Joy.
I did notice that the windshield edge of the frame seems to have a lot of side to side play. Is this normal? Could something be binding? This edge gets about 45degrees out of storage compartment when it starts its bouncing mechanics. It also feels like the system is pulling it in both directions rather than losing pressure and falling back down and trying to lift again....ideas?

On the plus side, I did drive it today with the top down and had a blast on some twisty country roads!

 

[Lighthouse]

play in the frame and bouncing action

On the plus side, I did drive it today with the top down and had a blast on some twisty country roads!

That's great! We have the hard tops installed here for the rainy season until Spring...

I did notice that the windshield edge of the frame seems to have a lot of side to side play. Is this normal? Could something be binding? This edge gets about 45degrees out of storage compartment when it starts its bouncing mechanics. It also feels like the system is pulling it in both directions rather than losing pressure and falling back down and trying to lift again....ideas?

Let's cover this first. Yes, there is some play on the top from side to side, while it's moving. Don't know how much play you have, so I can't say whether it's normal. If you let go of the switch while the top is partially up, it should freeze in that position (as long as the ignition is on). You could then wiggle the top side to side and see if you find anything unreasonably loose.

Regarding the bouncing when the top is only partially out of the storage compartment, that could get triggered by the lid suddenly signalling that it is not fully open, so the controller stops raising the top in order to avoid a collision with the lid. I have seen this happening on a car that was previously rear-ended: the right cover lift cylinder's bracket was bent down enough such that it would get the limit switch to change position with only slight wiggling of the lid in its open position. However, the same should happen when you are lowering the top, so this theory may not get us very far in your case. The signal for an open lid comes from the black switch in the right rear of the storage compartment. Are you able to read codes in this section of the cycle?

You are writing that it feels like the system appears to be pulling in both directions, as opposed to falling back down and then trying to lift up again. Things could appear to happen that way on account of air in your system - I know you changed a few cylinders lately. Thus, when the system stops in the middle of the cycle, the top may actually bounce a little, and it may bounce unevenly on account of more air on one side.

Hope this helps in getting some unknowns out of the equation, so that we can focus on the error code regarding the cover lock afterwards...

-Klaus

[email protected]

 

[rlmcdan36305]

yes, it does stay in place with the key on....
no codes but that dreaded 2 flashes...which always returns...Ill look closer at that switch...
how long does it take to "bleed" out the air? Is there a recommended number of tries of cycling the top I should do to facilitate this?
Thanks again for all you do sir!

 

[rlmcdan36305]

yes, it does stay in place with the key on....
no codes but that dreaded 2 flashes...which always returns...Ill look closer at that switch...
how long does it take to "bleed" out the air? Is there a recommended number of tries of cycling the top I should do to facilitate this?
Thanks again for all you do sir!