Rear head rest
 

Hi guys,

My W124 rear headrest won't go down when i prss the switch what could be the cause of it? Can any guys can help me out Thanks

The easiest way to find the problem is to check the operation of the vacuum valve located under the rear seat on the left side. Check to see if you are getting vacuum to the valve (engine has to be running). If you are getting vacuum then you need to see if the switch on the dash is sending voltage to the valve when the switch is operated. If you are getting vacuum and a signal from the switch then the valve is bad.

If you bypass the switch and connect both ends of the vacuum line together, then start the car, the headrests should fall, otherwise there's a leak on either side of the line.

Rear head rest
 

Thanks for the help but i can't get any vacuum and i had another problem my rear sunblind can't be lower by pressing the switch seen like something get stuck in it but when i push the sunblind abit and it can fully lower by the switch what could be the cause anyone could help me out Thanks alot

95 S420

my rear headrests want stay up (they are not powered in this model) once I dropped them with the button, they are down but wont stay up.

the front headrests wont move up , only if I help them manually to move up.
but they would move down.

I can't help with the rear head rests, but I can for the fronts...

http://v12uberalles.com/power_head_rest.htm

where is vacuum sourced from?
 

Where is the vacuum sourced from for the rear headrests on a 1992 500E?

I am getting ready to pull the back seat on the car and would like to know where to start looking as the gas door does not work sometimes and was wondering if they shared the same source?

The car seems to have a rough idle and I think it started at the same time as the headrests.

Moose

All vacuum is ultimately sourced from the engine.

Really? No your pulling my leg!
 

I would like to know if someone can help me find where the vacuum circuit originates for the headrests.

rear headrests
 

I have a 86 300E, my headrests would not lower and found the problem due to a disconnected vacuum line behind the brake master cylinder. The line got disconnected while I was cleaning under the hood and all I had to do was reconnect. My headrests must be raised manually and the switch is only intended to lower to aid rear view visibility.

nac line
 

I found the same cluster of vacuum lines. I am leak testing them today.

I am able to suck down the lines downstream of the vacuum switch and then the dash switch will work but will not work again after restarting engine

Will test more today to find fault


I

Have a look here for vacuum diagrams for 500E.http://www.detali.ru/cat/oem_mb1.asp?TP=1&F=124036&M=119%2E974&GA=722%2E365370&CT=F&Cat=44S&SID=80
Cheers, Geo.

link
 

Thanks, I found the pump under the rr seat and will "leak down" the system as I think it is a fitting or actuator for the fuel door.

The vacuum for the seats is not where In can find it but I am searching the site you sent as I type.

Thanks for your help