300 SDL driver seat will not move back - PeachParts Mercedes-Benz Forum

latitude500 · #1 01-02-2008, 01:28 PM

Okay, I let my girlfriend drive the car and she is not 6.2 and 200 pounds, so she moved the drivers seat up a little. So know I'm having problems moving the seat back because the bottoms didn't want to work. Strange how they work one direction and not the other. I attempted to look under the seat, but nothing seems damaged.

Is there a way I can over ride it, or do I need to open up the door and repair or replace something.

Thanks

I feel like a giant in a toy car.

TX76513 · #2 01-02-2008, 01:34 PM

Usually the switch(s) needs to be cleaned, bad contacts. One the otherside since it's an SDL with the drivers door open see if the switch works.

Brian Carlton · #3 01-02-2008, 01:43 PM

Quote:

Originally Posted by TX76513

Usually the switch(s) needs to be cleaned, bad contacts. One the otherside since it's an SDL with the drivers door open see if the switch works.

Agreed.

In the interim, just move the switch carefully toward the desired position. It might make contact along the travel of the switch. Attempting this several times may get the seat to move once..........maybe.

DieselGuy53 · #4 01-02-2008, 02:30 PM

If the switch doesn't solve the problem (clicking sound when you test the switch), then the seat has to be removed (unbolt, disconnect electrical connectors on the bottom) and the steel cable that drives the seat motor has to be replaced. That cable is toothed and may have been sheared.

This is what happened to mine and the fix was to replace the steel cable. BTDT...

Brian Carlton · #5 01-02-2008, 02:38 PM

Quote:

Originally Posted by DieselGuy53

If the switch doesn't solve the problem (clicking sound when you test the switch), then the seat has to be removed (unbolt, disconnect electrical connectors on the bottom) and the steel cable that drives the seat motor has to be replaced. That cable is toothed and may have been sheared.

This is what happened to mine and the fix was to replace the steel cable. BTDT...

If you sheared that cable, the tracks are suffering from far too much friction. Thoroughly clean the tracks with acetone. To do that properly requires removing the tracks from the seat bottom. Then, when completely clean, add new grease to all contact surfaces. The reduction is friction is significant.

If you just replace the cable, you'll likely have to do it again in the not too distant future.

probear · #6 01-02-2008, 02:54 PM

My problem was solved by removing the plastic caps, spraying contact cleaner into the switches, and then cycling the switch a number of times. 90+% of the time, the switches are just corroded.

daw_two · #7 01-02-2008, 03:24 PM

For some reason, the switch would not raise the back....had the passenger seat in a reclining positon; but pressing the memory preset position, the seat went back to that position.

I haven't put the seat nor let anyone else recline in it since.....

DieselGuy53 · #8 01-02-2008, 09:34 PM

Brian Carlton,
In my case, it was not the switch. Both switches I replaced turned up perfectly fine after I discovered the cable had sheared. Ran to recycler and salvaged a couple of cables...(the fore/aft cable is longer than the up/down/recline cable). Poor me, destroyed some otherwise good set of seat motors out there...shhhhh!

Yes, I cleaned the sheared pieces inside the motors and tracks, re-greased them before reassembly. My seat worked the same way it rolled out from sindelfigen(sp?).

Hatterasguy · #9 01-02-2008, 10:03 PM

My passangers side seat used to do that. You need to remove the seat switch's pull them apart and clean all the contacts. Carefull those little balls and springs are a PITA!

If thats to much you can get new ones for like $100.

bulletproofair · #10 01-02-2008, 10:10 PM

You can easily test the switch (and maybe at the same time move your seat back) by pulling the plug from under the passenger seat and connecting some cables with alligator clips on the end to the corresponding pins (you can tell the correct ones by pushing the switch in the "back" position while at the same time taking a multimeter and testing each male pin to see which ones are producing the +12V and -12V). I forgot the pin #s but I just did this a couple weeks ago and its basically common sense stuff. Just jump (obviously the +12V and -12V which is the ground for that function) the 2 MALE pins on the passenger side plug with the corresponding 2 FEMALE pins under the drivers seat.

Hopefully you can understand what I just wrote. Its actually not bad.... Anywho this is how I discovered my driver's side seat switch was bad and at the same time was able to adjust by jumping pins from passenger side to the drivers side. Sometimes even if you think the problem isn't the switch it might be because contacts may go bad inside as other members have said.

Good Luck!
- James

chasinthesun · #11 01-03-2008, 11:24 AM

I made easy work of all my 300d windows ,only one was working .After unclipping the back of the switch ,take a rendering of all your wires locations.Tighten up slightly the female wire ends with some needle nose pliers ,then reattach the ends on to the switch and retry the piece.Worked for me on three windows.

DieselGuy53 · #12 01-03-2008, 02:20 PM

What I am suggesting (other point of view) is that sometimes seat switches and their electrical wires can be perfectly functional yet driver/passenger seat does not (fore/aft/up/down/recline).

This calls for further attention to seat motors (unless there is no foreign object blocking the tracks). I have seen seat motors burn or disintergrate. I have seen cables sheared and broken. This is what happened to my 126 and it was infact the fore/aft cable that sheared. Disassembled the motor, replaced, regreased the sheared cable, re-assemble and the seat works fine...

daw_two · #13 02-21-2008, 12:33 AM

Okay, guys, I have a new project. Bought another 300SDL last night, and while attempting to adjust the driver's seat, I learnd the reclining seat will lean back but NOT come back up. Of course, we all know about how the contacts sometimes don't complete the circuit, so I tried moving back a bit more then forward. Do you see where this is going? By the time I gave up, the seat is reclining so much, I'd have to use my foot to steer and I'm 6'2".

Is it usually the switch in the door? And are these easy to clean .....or gain access to?

Thanks! Oh, and my fix that I used on my other car to press the preset seat switch didn't work here. I have to wonder if the positions are even set.

Fun. Another project!!!

Brian Carlton · #14 02-21-2008, 12:58 AM

On the driver's door switch is a six pole plug. On the six pole plug is an orange wire which leads to socket #2 on that plug. Ground that socket and the seat back should magically rise.

You can take the switch apart.........carefully..........because all the springs want to go airborne.........and clean it. Or, a new one will do the trick for about $100.

daw_two · #15 02-21-2008, 07:37 AM

Quote:

Originally Posted by Brian Carlton

On the driver's door switch is a six pole plug. On the six pole plug is an orange wire which leads to socket #2 on that plug. Ground that socket and the seat back should magically rise.

You can take the switch apart.........carefully..........because all the springs want to go airborne.........and clean it. Or, a new one will do the trick for about $100.

Thanks, again, Brian!!! I knew one of the experts would know the "trick" to getting the motor to go in the reverse direction. The New Gal even has DASH Lights and orange needles on the gauge. I hope Madame doesn't get jealous.