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Discussion Starter #1
Hi,

I have the SL 320 -94 with the seat switch without the memory function.
I know that my seat switch for the driver seat is not working perfectlyin the past and I have been looking for a used PN 129 820 27 10.

Yesterday when starting driving the driver seat started to move forward during driving.. Quite dangerous..

But the only thing tha moved the seat was either moving forward or leaning forward, whatever you tried to do.

So now the seat is stuck in the most forward and lean forward position.

The wife can just squeeze in to move the car.

I started to warm up the car with heating fans as it is cold in Sweden now, as I have noticed this a few times resenty, and wonder about damp / cold with electronics and connectors.

I can now hear the sound of relays when trying to move the seat back, but I am not sure if it tries to move forward or back, as the seat is in the most forward position.

I read in other threads about the functionality of the seat to lean forward automatically when the seat is in the most backward position, and this could be the problem. But I didn't understand the solution.

I also saw the picture of all elecronics below the seat, and wouldnät like to dig into those..

Any suggerions?
Can you bridge the seat switch if you remove the switch from the door "clothing".
Any instruction on the removal of the door "inside" / "clothing", don't know the English word..

Thanks
 

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Discussion Starter #2
I find some instructions and managed to remove the switch from the door.

It is clear that the switch is broken as I could move back the seat when I had the switch out and could bend it a bit.
 

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I find some instructions and managed to remove the switch from the door.

It is clear that the switch is broken as I could move back the seat when I had the switch out and could bend it a bit.
Glad you have found a reason for the problem,the seat can be moved by hand if you remove the lower cushion ,2 screws to remove the cushion,have a look at my past posts as some kind member told me how to do it because mine had moved forward as far as possible due to the seat control box under the seat being wet :thumbsup:
 

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Before you start playing with the seat, look at the trunk fuses.

If you want to move the seat manually, with cushion removed, in front of the seat
you will see the motor with two rubber couplings.
To move the seat back turn them.

I don't remember about the tilt motor. :(
Memory is not up to par. Haha.

Regards,
aam.

Regards,
aam.
 

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I had the same problem with mine the switch would work when removed and put under pressure. At one stage I got wedged between the seat and steering wheel :D:eek: The 6 pins in the connector where rising when it was pushed together and not connecting properly. I put a small square of plastic between the pins and the black snap cap to take up the slack. I also re soldered the wires to the pins as some seemed a little dry. Problem seems solved.
 

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Discussion Starter #6
I had the same problem with mine the switch would work when removed and put under pressure. At one stage I got wedged between the seat and steering wheel :D:eek: The 6 pins in the connector where rising when it was pushed together and not connecting properly. I put a small square of plastic between the pins and the black snap cap to take up the slack. I also re soldered the wires to the pins as some seemed a little dry. Problem seems solved.
Hi,

Looks like we have the same problem.
Great thanks for guiding me in this direction.
I don't exactly understand your description, but it might be because I have the switch without the memory.

I attach two pictures for description.
1. did you dissemble more? If so, how did you get the circuit board out?
2. where did you solder and put the piece of plastic?

Thanks

/Jonas
 

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It's been a while but if I remember right, when you take the door switch out the wires that go into it consist of a black connector with six pins. You can lift the cap off the connector to remove the wires and pins. The pins on mine tended to be slightly loose in the connector, so when the male part of connector was pushed into the female part of the door switch the pins did not seat properly. I re soldered the pins and put a small piecee of plastic about 10mm sguare on top of the pins before closing the lift up cap on the connector. This made the pins more rigid in the connector and created a better fitting connection. Sounds more complicated than it is.



I used a bread bag tie as pictured it was the perfect size (ignore the use by date) :D
 

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Discussion Starter #9
It's been a while but if I remember right, when you take the door switch out the wires that go into it consist of a black connector with six pins. You can lift the cap off the connector to remove the wires and pins. The pins on mine tended to be slightly loose in the connector, so when the male part of connector was pushed into the female part of the door switch the pins did not seat properly. I re soldered the pins and put a small piecee of plastic about 10mm sguare on top of the pins before closing the lift up cap on the connector. This made the pins more rigid in the connector and created a better fitting connection. Sounds more complicated than it is.



I used a bread bag tie as pictured it was the perfect size (ignore the use by date) :D
Hmmmm.

I am leaning against the sulution that you describe.
That the female part of the connector is not working perfectly.

The problem with that conclusion it the fault both you and me discovered, namely that the seat started to move by itself.
It points in the direction of the switch rather than the connector.

However, I will buy some connector spray and clean the connectors during weekend.

Thanks but confused on a higher level..
 

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Discussion Starter #10
I found one hint in another thread and that was to solder again on each pin.
This now worked for my Left side.

Will try the same on the right switch.
Hope it helps other with the same problem..
 

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We just addressed this:

VEHICLE: 1995 SL600

SYMPTOMOLOGY: DRIVER'S POWER SEAT MOVES FORWARD/TILTS FORWARD ON ITS OWN WHEN IGNITION IS TURNED ON AND DOOR IS CLOSED AND DOES NOT STOP.

BACKGROUND: (5) DIFFERENT SOCAL MBZ SHOPS HAVE ATTEMPTED REPAIRS UNSUCCESSFULLY - DISCONNECTING POWER SEAT SWITCH HAS NO EFFECT.

REPAIR HISTORY: POWER SEAT SWITCH AND POWER SEAT CONTROL UNIT RECENTLY REPLACED WITH BRAND NEW MBZ COMPONENTS.

TECHNICIAN'S FINDINGS: REMOVE SEAT FOR TESTING. CONDUCT PIN-BY-PIN TESTING. DISCOVERED FAILED SEAT BACKREST RELAY MODULE (DRIVER'S SIDE) PART # 129 821 00 47.

ACTION TAKEN: REPLACED MODULE # A 129 821 00 47. SEAT NOW FUNCTIONS NORMALLY. ALL THREE MEMORY PRESETS CAN NOW BE PROGRAMMED.

TOTAL TIME CHARGED: 5 Hours
 
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