C140 Rear Headrest passenger side will not lower - PeachParts Mercedes-Benz Forum

Nexisone · #1 06-02-2006, 04:45 PM

I hit the switch and it makes a lot of noise but it will not lower. The drivers side rear headrest operates normally.
I really need to lower this headrest in order to put the seat back in. Also I would like to know how to remove the headrest pad as to remove the rear parcel shelf.

Nexisone · #2 06-08-2006, 03:59 PM

No one has a manual or any prior experience on these cars? How about a manual someone want to sell me a manual or copy of one?

bhatt · #3 06-08-2006, 04:13 PM

I just bought a W140 so I'm flying blind here, but....

Do you have a rear seat switch to put the headrest down? As in a button the rear passenger can use to operate it? If so, try that button.

In my car, the dash switch only ever worked once to move the left rear headrest. Right rear works all the time.

However, if I use the button on the left rear door, it works just fine. I think there is an issue with the dash switch.. perhaps I need to clean it.

Do you hear a noise when you push the button (motor running) or is it silent (electrical problem)?? That would be a good place to start looking.

Neal

gurban · #4 06-08-2006, 08:52 PM

I have a w140. Seat back has to be forward a little on my car to move the head rests. Also, the back switches seem to be more dependable than the dash one. On one of the answers to my questions someone gives the procedure to get to that mech. No a nice job I'm afraid.

Gary

Nexisone · #5 06-09-2006, 02:34 PM

Passenger side motor makes noise but doesn't lower the headrest. I am looking for a way to manually lower it.

KenP · #6 06-10-2006, 06:41 AM

I'm assuming that your description of "C140" is a W140 Coupe.
I've had my rear head rests apart. Its a bit tricky and the Mercedes shop documentation doesn't help much. Shop diagrams show it as a vacuum controlled mechanism; my '96 is electric.
Because you say the mechanism makes noise, I suspect its electric also.
The mechanism is nothing more than a small electric motor that drives a plastic gear reduction mechanism. My guess is that either the head rest got stuck, or it got sufficient force to strip one of the gears in the reduction gear train.
The mechanism is all one assembly and is located directly below the headrest.
After the upper rear seat cushion is out, you can access it but its not easy. Its behind a steel support.
The head rest itself is removed along with the two curved supporting rods. The ends of these rods go thru the rear parcel shelf as you already noted.
Where these rods attach to the lowering mechanism, there are spring clips. If you get a small mirror, you can see them. Release the clips by feel and the rods will be free to be pulled up and thru the parcel shelf. Again, you don't take the headrest off the rods; they come out together. Once the headrest is out, the parcel shelf is easily removed.
Good luck. My guess is that you'll need to take out a second loan against your house to buy one of these things... all for the sake of a small plastic gear.

Nexisone · #7 06-10-2006, 01:57 PM

So is the lowering mechanisism on the motor? Is it one piece and the rods need to be unclipped? The two giant phillips screws hold the motor to the bracket?
I think I found the most irritating repair on the car.

A. Rosich · #8 11-13-2007, 10:08 AM

Quote:

Originally Posted by KenP

I'm assuming that your description of "C140" is a W140 Coupe.

Just to clarify, the correct factory designation to the 140 Coupe is C140. W140 ONLY applies to the sedan.

wallfly · #9 09-02-2007, 12:19 AM

A bit late for this but it may help someone down the road. I have a problem with the rear head rests not dropping when I push the dash button. Mine is vaccum operated. The valve which converts the electric signal to pnuematic is located under the rear passenger seat /drivers side. My car is a 91 300d.

gurban · #10 10-16-2007, 01:18 PM

Has any one ever seen a repair kit for the plastic gears?

kanio · #11 11-13-2007, 01:23 AM

my 95 W140 is having problem on the rear head rest. The passenger rear headrest goes up and down with bunch of clicking nose when it is about to reach the final position. The driver side doesn't work at all. Is mine all electricial?