DarkRothaus

Hi,


I know there are a couple of threads out there around these issues.
Just wanted to make sure my theory is correct before spending unnecessary money on one of the limit switches.

• CLK500 MY05
• 109k miles

My soft top worked without any issues until two days ago.
I opened it in the morning and when I got to work, it wouldn't close anymore.
Since I'm familiar with the threads around leaking cylinders etc., I was prepared for the worst - but:

• checked hydraulic fluid level:
  • top up: Exactly between min and max
  • top down: Pretty much at max
• checked error codes with DAS and at first didn't have any
• tried to close the top a number of times, pulling the switch, then pushing etc. - relais were always audible, the pump for a second or so whenever I pulled (open)
• at some point it closed and I was able to get it to open and close a number of times with the process stopping at various positions - usually the cover would open after a few attempts but then stay there and the top wouldn't be pushed out, or for the opening procedure, it would just lower the windows and then not do anything
• checked for error codes again:
  • Found B1928 "Stored" and after a couple of times also "Stored and Present" "Limit Switch INTERLOCKED of soft top compartment cover remains in switched condition"
• today I was trying to see where the S84/13 switch would sit and therefore opened and closed a few times
• then I also got B1923 "Limit switch catch position of soft top cover fails to switch" which relates to S84/22

I then tried to troubleshoot S84/22 and even with the error code only "Stored" and not "Present" I got these results with the top fully closed:

• convertible top compartment cover closed = NO
• soft top compartment cover raised = YES
• convertible top compartment cover open = NO

Does this combination of values make any sense for the top completely closed?


So here is where I want to double-check my assumptions:

• I shouldn't have any leaks since the level looks good?
• The hydraulic pump seems to be OK since it works fine WHEN it works?
• The relais for the hydraulic pump should be OK since they work WHEN they work?
• S84/13 seems to cause problems since it showed up multiple times as an error and also since the status I mentioned above doesn't make sense?
• S84/22 might have an issue too, but since it only showed up once, I'm not too worried about it right now?

This got a little lengthy..
Any ideas as to how I should proceed?


Otherwise I'd probably go ahead an order the S84/13 and hope it is the faulty one. It's listed with EUR 63 + VAT in EPC, so it's probably $1xx I guess.


Thanks,
Patrick

Top Hydraulics

Patrick,

If I'm not mistaken, then switch S84/13 is the plastic switch assembly that clips onto the left tonneau cylinder A 209 800 12 72. It signals whether that cylinder is extended or retracted. The part number for this switch assembly is A 209 820 18 10, and the price you are quoting would match how much that assembly costs in the US.

Before you buy the part, check first whether it is possibly just dislodged a little from the cylinder. The main part of the switch assembly attaches to the cylinder body, and the sliding part clips onto the end of the moving cylinder shaft. If the switch is attached correctly, then you may want to take it off next and examine it more closely. It is a pretty simple assembly. Once you have taken it off, you will see two micro switches inside that get triggered by the moving plastic. Figure out why they are not triggering or getting stuck, and see if you can't just fix that. Please take a photo of the inner workings and their failure while you're at it, and post it in a response, if this helped...

Regarding S84/22, that's one of the two switches in the left forward bracket that the tonneau cover lands in when it closes. It is quite common that they fail or don't get fully triggered. Take a look if they are properly seated, or if one of the plastic switch housings is cracking. If you find a problem there, please document it with a photo for future readers...

Hope this helps, and please keep us posted,

Klaus

www.tophydraulicsinc.com

DarkRothaus

Hi Klaus,

Thanks for your reply!

I should have added to my post that I

- Identified where these two switches are (happy to take photos)
-- Manually opearated S84/22 (at least I did hear it click and it didn't get stuck anywhere)
-- Manually opeated S84/13 by unlatching it from the sliding part. For this one I also noticed the click in the extended position as well as the other click as soon as it reaches the retracted position.
- Similar to our beloved brake light switches the fact that they click probably doesn't mean that they're not broken.

I'll try to remove the S84/13 from the car then.
I guess I'll have to do that with the top closed and try to unlatch it from inside the trunk. This might be a little tricky but I think I can get there with my not so tiny hands

Thanks again - that's good confirmation that I'm going after the right things
Patrick

Rudeney

It sounds like you have your own copy of SDS. If so, you can use StarFinder to access photos of these parts. Klaus, as usual, has offered good advice on located these switches:





S84/13





S84/22

DarkRothaus

Thanks Rudeney, yes I identified these guys, thanks.


I just removed S84/13 from the car, took it apart and checked the two little switches inside with a multimeter.
At least here on my kitchen counter - they seem to perform as expected. That probably doesn't necessarily mean that they'd never act up while in the car, but they seemed to be reliable on multiple occasions.


I should add - reliable in terms of I can see resistance indicated on my multimeter vs. nothing at all. Not sure if they're supposed to indicate a specific resistance.

Here's a photo of the two microswitches, the right one does the extended end-position, the left one is for when it's retracted.

DarkRothaus

Didn't have time to work on the car the last couple of days and got back on it today.


First thing I did was reading the fault codes from the soft top module again.
Besides the B1923 and B1928 I had last time, I also got a B1924 now.


I guess those had just been caused by the testing last time when the top remained in an unusual position for a longer time maybe.


So I cleared the fault memory and tried to operate the top.
Guess what, it worked. It worked three times straight without any error codes.


Now that's the kind of result that makes me feel really confident that it'll work reliably from now on and forever...


I'm sure there is going to be an update to this not too far from today..

Arie Schaap

Hello,

Is what you can see in this video the same as you observed?

First cycle goes ok, than it gets stuck. Currently it does not move until half way up while the motor runs and the other cilinders are pulling.


https://www.dropbox.com/s/ldet5qkpru5x0xv/2015-09-23%2015.41.12.mov?dl=0[/URL]



Arie

DarkRothaus

Hi Arie,

It seems like the positions where your's gets stuck are a little different to where mine got.
Would be interesting to see which error codes you have in the system.

From the looks I'd guess that this might well be another case of one or multiple sensors acting up and not allowing the process to continue.

In my case, I couldn't really find a root cause. I did however manage to somehow leave my control unit in diagnosis mode which drained the battery completely. From that point on, I never had an issue with the roof again. It seems that my control unit just hung up badly.. not a great explanation, I know.

Good luck!
Patrick

Jayson916

Thanks folks! Super helpful thread!

My 2098201810 switch had failed internally. Once I identified it, the swap was easy. I made a video but it’s not great quality. (I’m terrible with a camera).