1999 CLK 430 Driver Seat Stuck in Forward Position
 

I hope someone can help me with this soon as I am stranded at home unless I can figure something out.

I have a 99 CLK 430 and last week the wife took it so I can do maintenance on her car, and she moves the seat forward. Later that night I move the seat back before getting in and after sitting down I tried to move the seat a bit forward but all it did was click. Forward and back just makes a clicking sound. Up, Down, and backrest adjustments works fine. The next day, I checked the fuses under the hood and in the trunk, and inspected underneath the seat to see if anything had been disconnected, or if there were any obstructions. Fuses were good, wires and plugs seem fine, and no obstructions. Still no forward or back...just clicks (sound like the switch is fine, relay seems to be working). I read other threads that talked about the control module, motor, and track. So I was gonna check that out the next day.

Next day, I take the car out and the seat works fine. Forward and back worked. When I get home, I figure I'll go ahead and clean the track in case that was the problem. I move the seat all the way forward to get better access and clean the track. Then it goes out again. Now the seat is so far forward I can't even get my legs in let alone drive the car. I dont even think my wife who is 5' 2" can safely drive that car with the seat so far forward.

Any ideas. If it is the module, track, or motor, does anyone know about the cost of repair (warranty is up). Also is there a way to manually move the seat back, or disengage the motor. Any assistance is would be greatly appreciated.

I had the same problem with my 99 CLK as well. Turns out the track was chewed up and couldn't go back because the a few of the "teeth" were mangled badly. I tried numerous things, but never got it fixed, b/c mine was stuck in my seating position.

You should try lifting on the seat while pressing the button on the seat (obviously not sitting in it). If not, through an independent, between parts and labor I was looking at ~$700. :smash:

update on this POS seat
 

Just an update on this POS seat. Since it was stuck in the furthest forward position, I took it to a shop that took it apart and put it back together again. They said that sometimes the motor just seizes and needs to be "unseized".

They took it apart, put it back together again and it works. But I figure it is the worn out track that causes the motor to get stuck. So now I just do all I can to not move the seat. By the way. It has gotten stuck and unstuck on its own a half dozen times in the last few months.

Conclusion: If its stuck in the furthest back position, I'm driving. If its stuck in a forward position, the wife is driving.

:bs:

I have the same issue with my CLK55
 

I am going to dive into tonight.. Taking the seat out to see what the issue is.. My wife is 4'11" and I am 6'2"... I let her drive it one day and it was stuck in the forward position.. I hear the relays clicking but nothing else.

Just happened to me again yesterday. If you've verified that its not the fuse in the trunk, take a hammer and tap the motor :X (the one furthest forward under the driver seat) while hitting the switch. That should do the trick in getting the motor unseized.

Let me know if that works for you.

By the way...you dont need to remove the seat to get to it with the hammer. I just raise it up and it doesn't take too much leverage. This is just like banging on a starter to get the engine to turn over. A couple taps is usually enough to get it going again.

What a life saver...
 

It worked.. awesome.. Someone needs to post this in the DIY...

I will try this thanks.

I have a strange seat problem as well. My seat will move front when I press back and can't get it to move back at all. Luckily the memory is saved to go all the way back and to my normal driving position. I'm pretty sure it's not the motor or the track since it works when using the memory. I'm thinking about replacing the seat switch. Anybody know how to take the seat switches off so I can take a look at it before replacing it?

Thanks in advance.

I tried this last night and no luck. Although I wasn't entirely sure what to tap- Does anyone have a pic? Does it have to be tapped while pressing the switch?

There will be three motors underneath the seat, so just gentle tap them :rolf:

Before anyone goes and pays to get the seat fixed has anyone pulled the fuses from the trunk to ensure that the fuses have not just blown??

I guess its possible that your motor is so shot that this will not work for you. There are three motors under there. The forward/back motor is the one sitting towards the front left. Usually a couple hits with the hammer is good enough for mine. I usually tap the motor while hitting the switch, but when I first discovered this quick fix I just tapped the motor thinking that it hit a bad spot on the track, then when I got back to the switch everything was functioning fine.

By the way make sure the fuse in the trunk (#9?) is not blown. I think the head rest controls don't work as well as the forward/back when that fuse is blown. Good luck.

https://mbworld.org/forums/showthrea...678&highlight=

Just one burnt tracer and leg of this part kept me from leaning my seat forward and backwards. When I switched the plugs on it which changed the outputs and inputs, it then stopped me from moving the entire seat forward and backwards rather than just the upper back, BUT I regained the ability to move my upper seat which was the original burned output and tracer. Some of the plugs are possible to switch if you are in a bind and need a quick fix.

it's under the front of the drivers seat.

Moral of the story: Whichever leg goes bad on that output determines what function you lose on the seat. SOME of the plugs are identical in wire colors and can be swapped to regain functionality of another section of the seat you need more than whatever is currently working.

It's a series of identical inputs and outputs, the only thing that determines what it does is the position of the plug.

Lastly, on some occasions simply unplugging the unit (power plug, larger wires on this plug) for 30 seconds and plugging it back in gives it a reset and provides one pressing of the button to move the seat before it goes back into protect mode on that output.

Did you end up soldering on a new chip or replacing the part?

I pulled my module out as well and noticed the exact same middle leg was missing but when taking a closer look it doesn't seem like it was ever soldered on the board to begin with.

Has anyone tried to replace or reconnect this part?

Please let me know as this seat problem is driving me nuts!

I tried the fuse and it worked for both seats the forward and back then the driver seat stopped again so I think its the motor so ill try tapping it and get back to u guys

2 weeks ago my driver seat got stuck again. For the first time since I discovered the "tapping it with the hammer technique", it didn't work... However, pulling out and plugging back in fuses 6 thru 9 in the trunk did the trick... Over the last couple years, a couple taps with the hammer has worked 100% of the time. I guess this time, the system just needed to be reset or something and it wasn't the motor seizing up. Good Luck.

I just had to replace the fore/aft motor in my '02 CLK55 (did it myself). It got the seat moving again, but it still wouldn't go forward past a certain point even after I pulled the fuses and put them back. It would go a little farther forward by pushing the #2 memory button than it would by just pushing the regular forward button (memory setting must have been a bit further up). I then pulled the harness connector off the front of the control box under the seat for about 2 minutes and then reconnected. Everything worked fine after that except the seat wouldn't automatically move forward or backward when folding the seatback all the way up (ie. to let someone in or out of the backseat). I checked the manual and it said after battry has been disconnected or there has otherwise been a loss of electrical power, to move the seat all the way forward and put the headrest all the way down, then hold both of those controllers forward and down respectively for 2 seconds to reset the automatic forward and back (& headrest auto up and down). It worked - everything is back to working as original.

my seats wont move forward or backwards..
 

I do not think the gears are jammed. I took the seat apart and detached the motor from the gears and tried moving it but the motor did not run.. all i heard were clicks. I tried turning the gears on the motor from where the motor attaches and it turns very easily, looks like it doesnt take a lot of torque to get it turning.. So I think the control module is malfunctioning to where it wont give power to the motor....I will see how much it cost and try replacing it. Or hmm it could just be the motor.. wanna see if i could manually supply power to it without going through the control board but there are 5 or 6 wires so i have to find out how to supply power to it. I was hoping to swap motors but the one thats not working has diff number of wires than the others. So couldnt do it for fear that i could burn something.

Issue same but passenger side
 

Reply to POPTOPCLK
 

I just replaced the motor and my seat works normally now. You need to remove the seats cover panel on the side of it. There is one screw to remove near the back of the seat. Once the screw is removed. push it up and forward and out. Dont pull first at the front like i did and break the plastic finger/hook. Onces that is removed, there will be two "star" torx screw to remove, so that you can fold the seat up torwards the back rest. Look under the seat at the front and figure out which one. The one at the shifter side is a tough one to remove without the right tools.

From there you can acces the motors.

When you here clicks and it doesnt move that means the motors dead or the gears are jammed. more than likely its a dead motor. Tapping on it use to work for me, until the motor just couldn't turn any more. I actually got the problem motor turning with out mounting it, but it just jammed again. I wanted to take it appart and lube it or something but its just not worth it for me. too much work. For those who don't want to buy another motor you can swap the front up and down motor and put it on the forwards and backwards. Make sure you adjust the position of the up and down position before removing that motor. Then you'll have to get used to press up on the control to go forward. I did that just to move the seat foward to the correct position. Should have done that a couple days before so I wouldnt have to put two pillows behind me to reach the pedal!.

I don't think you need to get the passenger seat out if you are just to replace the motor. If you still need to its the four in the corners. The seat has to be moved in the middle to expose the back bolts. Its just four bolts in the corners.

just replace the whole motor assembly, that way you won't have problems with any of the 3 motors. My buddy might have one for sale. pm me so I can check with him

Temp Fix for seat not going forward and back due to a shorted motor.
 

Just temporarily got my seat forward and back working by switching the motors.
Here is a few notes:

The motor for forward and back is the middle motor.

To get to the motors :
1) I took off the left side cover with a single Phillips screw going into the back (The head faces the back of the car) and pulling the back end towards the door then forward to unhook it from an slid in tab.

2) The rest of the screws were #HH25 Torx screws.

3) I found it best to remove the 2 screws that hold the seat bottom cushion and it's bracket from the drivers side and a 3rd one AFTER I did the next step because I could not get between the seat and the console to get the inner screws.

4) The whole seat comes off with 4 #10MM bolts inside the track center at all four corners and it makes it easier to get to the bottom motor screws.

5) Once the complete seat is loose (Except for the wiring harness and a vacuum hose) you can get to the front seat cushion screw between the seat and the console. I could not seem to get the back one but with the other 3 off, I could lift the cession enough top get to the top motor screws.

6) Then I could remove the motors.

I did not undo the motor wire harness but I switched the running rear motor with the burnt center motor.

So, for now the button that should raise the rear of the seat instead runs the seat forward and back. Till I get a new motor and switch it out.

Marcus I wish my dealership offered prices like yours does, $128 bucks is awesome.
I checked at mine and they want a bit over $200.