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Discussion Starter #1
Hello folks,
our '94 280 Sl has been in the garage for service. There the battery went dead and after recharging the battery, this problem began. When we close the drivers door the window doesn't close the last inch. So we tried resyncing the windows, the passenger side works fine after that but no reaction on the driverside. It doesn't close completely when you try to close it by meaning of the window-switch neither. So several attemps of disconneting the battery and resyncing later I'm looking for suggesions on where to look for resolving this problem. When I measure the current on the the two screws connecting the windowmotor to rest of the car I have a 12 v voltage flowing when opening and closing but the voltage cuts of before the window is completely closed. No reaction occcurs when pulling the outer door handle so no pulse is given to open the window in order to clear the rubber surround. I assume there is a switch in the doorhandle mechanism that activates the motorcontrol to clear the first inch so opening the door becomes possible. In order to close the window the last inch when the door is closed there also must be some kind of activator. Anybody has some insight in where to start looking for this troubleshooter, the garage looked for it for several days but couldn't solve the problem? This help would be very appreciated. Greetings from Belgium.
 

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03 SL Kleemann, 97 SL320, 95 E320 cab, Tesla X, Ferrari 360, etc
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Unsuccessful window synchronization after the battery was dead?

Hello folks,
our '94 280 Sl has been in the garage for service. There the battery went dead and after recharging the battery, this problem began. When we close the drivers door the window doesn't close the last inch. So we tried resyncing the windows, the passenger side works fine after that but no reaction on the driverside. It doesn't close completely when you try to close it by meaning of the window-switch neither. So several attemps of disconneting the battery and resyncing later I'm looking for suggesions on where to look for resolving this problem. When I measure the current on the the two screws connecting the windowmotor to rest of the car I have a 12 v voltage flowing when opening and closing but the voltage cuts of before the window is completely closed. No reaction occcurs when pulling the outer door handle so no pulse is given to open the window in order to clear the rubber surround. I assume there is a switch in the doorhandle mechanism that activates the motorcontrol to clear the first inch so opening the door becomes possible. In order to close the window the last inch when the door is closed there also must be some kind of activator. Anybody has some insight in where to start looking for this troubleshooter, the garage looked for it for several days but couldn't solve the problem? This help would be very appreciated. Greetings from Belgium.
bartbx,

welcome to the forum!

There are some major differences between model years '94 and '95. What may be called a '94 model in Belgium could already be called a '95 model in the US.

Let's clarify first which kind of control system you have: On the side that works, does the window drop automatically by a fraction of an inch when you open that door? (In the US, that starts with MY '95, made already in early '94...)

If you don't have the automatic window drop (model years '90-'94), then the window position is determined by limit switches inside the door, and no synchronization is needed.

Looking forward to your response,

Klaus

Top Hydraulics | Rebuilt Convertible Top Hydraulic Cylinders - Top Hydraulics, Inc
 

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Discussion Starter #3
Thank you already for your help, now this car does have automatic drop down, with one push the windows open completely. On the passenger side everything works ok, but on the driverside the window does not close completely nor does it lower itself a part of an inch to clear the window from the rubbersurround. Trying of resyncing doesn't solve the problem. When I close the door I can't close the window completely with the windowbuttons. This car was brought here because the guy who worked on it couldn't resolve the problem, I can't contact him before 8/8 because he is on holiday and the owner of the car can't use it like it is now beause of the rain pooring down constantly and with a window that doesn't shut completely...
 

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03 SL Kleemann, 97 SL320, 95 E320 cab, Tesla X, Ferrari 360, etc
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model year '94 in Europe can equal model year '95 US

Thank you already for your help, now this car does have automatic drop down, with one push the windows open completely. On the passenger side everything works ok, but on the driverside the window does not close completely nor does it lower itself a part of an inch to clear the window from the rubbersurround. Trying of resyncing doesn't solve the problem. When I close the door I can't close the window completely with the windowbuttons. This car was brought here because the guy who worked on it couldn't resolve the problem, I can't contact him before 8/8 because he is on holiday and the owner of the car can't use it like it is now beause of the rain pooring down constantly and with a window that doesn't shut completely...
Thank you for clarifying that you are a shop. I appreciate your candor.
If I understand you correctly, then you have the function where the windows are supposed to drop a fraction of an inch to clear the rubber weatherstripping. That would qualify your customer's car as a '95 model in the US. You should still be able to read codes manually. Please read the archived threads on reading codes for the controller in the "stickies". Please let us know what you find out when reading codes...

By the way, did you apply voltage to the window motor leads only to see if it will go up all the way, and to see if it will then always go up as high? (I would separate at least one of the leads going to the controller for that test.)

To answer your previous question, the signal for an open door comes from a switch related to the door lock mechanism inside the door.

I hope this helps,

Klaus

Top Hydraulics | Rebuilt Convertible Top Hydraulic Cylinders - Top Hydraulics, Inc
 

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Discussion Starter #5
I'm a car audio dealer, this problem has nothing to do with my business, but this customer bought his audio here and he already had some minor issues with his car that I solved during installation of his audio system. He now asked me to look into this problem because his maintenace garage is closed for holidays and they already searched a couple of days to find the problem. So it is more a service to a good audio customer and I tend to search till I find the problem. This morning I disconnected the batteru
y and on first operatio I could close the window completely but after several attempts the window stops a fraction of an inch from the top, quick down works fine, just the automatic lowering to clear the rubber doesn't work.
 

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03 SL Kleemann, 97 SL320, 95 E320 cab, Tesla X, Ferrari 360, etc
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this customer bought his audio here and he already had some minor issues with his car that I solved during installation of his audio system. ... This morning I disconnected the batteru
y and on first operatio I could close the window completely but after several attempts the window stops a fraction of an inch from the top, quick down works fine, just the automatic lowering to clear the rubber doesn't work.
Ah, thanks for the clarification. May I assume that you had the door panels off to install different speakers?

There may be light in the tunnel, and you might have been right in suspecting the switch signalling an open door. If the controller gets an erroneous signal that the door is open, it will of course not roll the window up all the way.

Klaus

Top Hydraulics | Rebuilt Convertible Top Hydraulic Cylinders - Top Hydraulics, Inc
 

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Discussion Starter #7
Indeed I did have the door panels off to change the speakers but this was 15 year ago, everything worked fine untill the other guys drained the battery, fuzzed around with the sync system, did maybe other things I'm not aware off but then turned to me for help. I checked some things but I don't have the electric schemes of this car and I do suspect or the central control unit of not receiving a pulse to clear or close the window or a sensorswitch not giving this pulse. Have you got an idea which colour coded wires go to the suspected switch? And what sort of signal is transmitted, a negative pulse or positive. I found one wire giving 0,130 volt which dissapears if you unlock the door
 

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R129 SL320 1998
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I have same problem with my '98 sl320,
it took dealer 4 hours to determine it was some kind of microswitch
in door lock , the microswitch in door lock sends signal that doors are shut or open and the dealer wants 300euros for the whole door lock.
Is there a way to change or clean microswitch ?
 

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Discussion Starter #9
I haven't found that switch yet, I think we have to take the whole mechansm out of the door in order to see more. I might think the microswitch is build in into the lockmechanism surround. So I would unstall it if I could first determine if this is the reason for the wrong behaviour. A scheme would give us an idea of the signalsort or measurable data going to it and away from it. It can be a simple on/off microswitch with a voltage going through it or a groundbased wiring diagram, really no idea at the moment. Think I'm going to sent this guy to an official dealer to collect a printout of the electrics involved. Some logical thinking must locate this switch to be in the door opening mechanism because the function has to work from entering through the outside as well as leaving from the inside.
 

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Discussion Starter #10
So I did some reading in the classifieds and came to the following conclussion (correct me if I'm wrong). The chasisn° of this car begins with 129.058 and it has the round 38 pole diagnose plug, so on this particular model there is no pin which can give the faultcodes for the CF (convenience feature) and the power windows related codes are mostly situated under this topic. I think I've to interprete that on this model there is no fault diagnosis for the convenience module like on other mercedes models or that the way the power windows are regulated isn't controlled by the cars system. So back to my first idea a bad behaving sensorswitch in the doorhandle mechanism?

Has anyone a picture of the doorlock and surroundings, so that I don't have to take this thing apart just to find out you have to replace the mechanism as a whole unit. If the switch would be a seperate part maybe we can find a solution to just replace the switch.
 

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R129 SL320 1998
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Seems to me that the dealer said that microswitch is located in part number 5 in this scheme
Is there a way to change it without changing the whole mechanism?
 

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1998 SL500, 2010 GLK 350, 1972 300SEL 4.5, 1971 280SL, 1970 300SEL 6.3
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I had this same problem on my '98. Resynch did not work. I could not find the microswitch to change out. However spraying the lock mechanism with WD40
solved the problem. It may be worth a try.
Baybear
 
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