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.

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?

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

__________________
'83 300SD 335,000km (207k) mi SOLD
'87 560SL 163,000km (101k mi) SOLD
'86 300SDL 356,000km (220k mi) SOLD
'92 500SEL 250,000km (155k mi) SOLD
'90 300SL 140,000km (87k mi) SOLD
'01 S430 260,000km (161k mi) SOLD
'03 SL500 167,000km (104k mi) SOLD
'07 S550 4MATIC 235,000km (146k mi) SOLD
'07 GL320 CDI 4MATIC 348,000km (215k mi)
'13 GL350 BlueTec 4MATIC 170,000km (105k mi)
'14 SL550 72,000km (43k mi)

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

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

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.

__________________
KenP

1996 S500 W140 Coupe

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 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.

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

__________________
grurban@wi.rr.com

1972 280SEL 4.5 245,000 sold
1994 S500 172,000

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?

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93 Toyota Corolla 177K
95 S 500 coupe 82K
92 400E 180K (SOLD)
94 E 420 150, blown gaskets (SOLD)
http://www.kanio.net/mercedes_signature.jpg

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

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A. Rosich
CL 500, 1998
S 500 L, 1998
E 320 T, 1995 [Sadly sold ]

I guess everyone got discouraged on this one. But I did succeed in removing the headrest mechanism on my '96 S500 coupe. Alldatadiy has the procedure for a sedan. Duh - the picture has a door in front of the C pillar.

1. Remove the seat backs on both sides. Put the headrests down first. If you have one locked in the up position, you are going to have to lift up one side at a time and pull out, both forcefully.

2. Remove all forward-facing screws and lift out first-aid compartment.

3. Look at the sides of the unit you want to remove. On each side there is a white disk with a lever. Forget the mirror, they are in plain sight. You need to push one lever toward the rear while simulataneously pushing the that side of the headrest toward the rear. Repeat on the other side. Unless you are very strong, you may not be able to push hard enough on the lever to release the headrest. Fortunately, there is a slot in the white disk where you can insert a stubby screwdriver to gain additional leverage.

4. Surprise. There are four screws that need to be removed. Two in front and two in the rear under the package shelf. With the first aid kit removed, you can get the package shelf cover up just enough to get at the rear screws. I used a stubby screwdriver with vice grips on the handle to get the rear screws out.

5. My problem is that the driver's side headrest will not go down. There is a latch mechanism that locks the headrest in the up position that is not releasing. Not sure if it's repairable, but it's looking grim.

6. There are two different PN's for the assembly. The breakpoint is chassis 275889. Right and left are the same PN.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe