SL-Class (R129) 1990-2002: SL 280, SL 300, SL 320, SL 500, SL 600, SL 60 AMG

SL/R129: Soft top control module advice needed

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Old Sep 24, 2011 | 07:33 AM
  #1  
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1996 sl500
Soft top control module advice needed

Hi, does anyone have any experience in opening a 1996 sl500 top module and replacing the Zener diode and capacitors? I read about this on a MB forum once but can't find the exact article. The post stated that's typically what goes wrong with them. I've tried that sort of thing before and found the internal parts had their numbers changed and it was very dificult to match them up with replacement components. Thoughts anyone?
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Old Oct 4, 2011 | 01:19 PM
  #2  
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From: On the beautiful Oregon Coast
03 SL Kleemann, 97 SL320 pano top, 95 Lorinser E320 Cabrio, Ferrari 360, Tesla X
control module repair

saskjoe,

trying to repair the soft top control module can be very frustrating. There are very few posts on the net, and I think I know which one you are referring to. The modules changed over the years, with the most radical changes from MY '94 to MY '95, when the top controller assumed all roll bar controls and the drop function for the windows was introduced. Thus, parts have been changing a lot.

Some folks have been successful in finding cold solder joints (mostly on on the older ones), some have been lucky in replacing relays. Generally, you have a better chance at finding the problem on a pre-'95 controller.

Let us know what you find, and maybe some successful DIYers can post a few more remarks here...

-Klaus

Klaus Witte, Top Hydraulics, Inc.

We upgrade and rebuild top hydraulic cylinders for Mercedes R129, R170, R171, R230, W124, W208, and W209,
as well as Porsche, Rolls-Royce, Bentley, Saab, VW, Audi, and BMW convertibles
:thumbsup:

Also rebuilding convertible pumps...

www.tophydraulicsinc.com

Check out Mercedes-Benz convertible top hydraulic system diagrams and DIY instructions here:

http://tophydraulicsinc.com/faq.html



klaus@tophydraulicsinc.com

Last edited by Top Hydraulics; Oct 4, 2011 at 01:31 PM.
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Old Oct 9, 2011 | 10:58 PM
  #3  
lynns's Avatar
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From: So California
2000 SL500
RST controller rebuilders

Originally Posted by saskjoe
Hi, does anyone have any experience in opening a 1996 sl500 top module and replacing the Zener diode and capacitors? Thoughts anyone?
From MY96 through MY02 there are several p/n's for the RST comtroller's.

Example:

1298203126 1996 to 2002
1298203226 1995 to 1998
1298203926 05/97 to 2002

It's my suggestion that you consider sending your controller to http://www.benzworld.org/forums/2916113-post15.html

Please post on the cost and outcome of your repair!
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Old Jul 5, 2012 | 12:25 PM
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2014 CLS550 Bi Turbo
Great lead! Thanks much,

Joe B.
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Old Jul 13, 2012 | 06:39 PM
  #5  
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Smile

NG...BBA Reman had no luck, and is sending my 1298203926 back to me. Anyone have a spare one or suggestions???

Joe B.
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Old Jul 13, 2012 | 06:46 PM
  #6  
Top Hydraulics's Avatar
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From: On the beautiful Oregon Coast
03 SL Kleemann, 97 SL320 pano top, 95 Lorinser E320 Cabrio, Ferrari 360, Tesla X
Controller repair beyond BBA

Did BBA give a reason? We have a supplier who might be able to do more on late model controllers ('95+). No promises, but worth a try...

Klaus

www.tophydraulicsinc.com
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Old Jul 13, 2012 | 08:06 PM
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2014 CLS550 Bi Turbo
BBA stated that a relay inside the unit did extensive damage to the board. If you have a resource I would give them a shot, as long as they are reasonable.

Joe B.
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Old Jul 13, 2012 | 08:47 PM
  #8  
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From: So California
2000 SL500
Please read http://www.benzworld.org/forums/4083108-post11.html for a $400.00 RST Controller.
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Old Jul 14, 2012 | 01:04 PM
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1996 sl500
I replaced a swollen capacitor on my convertible top module but it still won't work. Is there a way to test the relays? And where is the best place to order new relays? Thanks, Joe.
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Old Aug 15, 2012 | 10:22 PM
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I have a soft top controller for sale model 1298203126
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Old Aug 16, 2012 | 02:56 AM
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From: So California
2000 SL500
Originally Posted by bbspoolside
I have a soft top controller for sale model p/n 1298203126
part no longer available but good for 1996 to ???? and replaced by -
p/n 1298203226 good for 1995 to 1998
p/n 1298203926 good for 05/97 to 2002

What's your asking price?
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Old Aug 16, 2012 | 08:35 PM
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2007 Gl450 2006 cls55
$350 plus shipping
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