W140 Closing Assist

[James Rothwell]

Is anyone familiare with the closing assist system on the 140?

My drivers door closing feature has stopped working which is pretty annoying as slamming the door is so terribly uncouth....

The pump has always made a noise once it's closed a door or a boot like a lorry releasing it's brakes. It is letting air out, is this normal? I can't remember if the last one I had did it or not but this one has done it for the last 4,000 miles and no problems with closing assist.

I've read most of the article on the v12 website, I'm going to try to pull out the fuse tommorow and see if that resets it, failing that I'll have to find time to get the pump out and mess with it, and if it is beyond repair I guess have to buy one or get one off a breaker.

Was the high pressure hiss after closing a door a sign that it was on it's way out?

 

[alexander patie]

assuming it works ok on the other doors then the reset will probably work. it may be a microswitch fault, but usually just an adjustment issue of the switch/door. getting at the unit can be a pain as it is tucked way forward in the boot n/s area behind a panel and encased in foam. the pipes make it even more awkward to access. try the reset, see how long it works then get back to us.

 

[alanuk400]

Is anyone familiare with the closing assist system on the 140?

This guy does
V12 Uber Alles, Getting to know your Closing Assist Pump in a W140 Mercedes Benz, an article by Brett Allison
Home
V12 Uber Alles, Repair Help for Mercedes Benz S600 V12 W140

Alan

 

[James Rothwell]

Taking out fuse 9 in the boot and putting it back in again works once and then it stops working again. Now the boot doesn't work either.

I think I'll have to follow that guide and get it out and try and repair it, sounds like a job for next weekend!

 

[BlackC55]

I suspect the pump is the issue. fairly common on the 140

 

[James Rothwell]

I suspect the pump is the issue. fairly common on the 140

If I follow the guide on the V12 website, will it just keep coming back again and again and with more frequent failures? Is it best just to get another pump?

 

[BlackC55]

Eventually yes. It is probably best to get a second hand pump as they 'aint cheap.

 

[James Rothwell]

I'll have a go at fixing this one and if I can't fix it or break it further I'll get one off eBay think I saw one on there a week ago for £150 + postage but I don't know how old it was.

 

[Dieselman]

Before condemning it it's got to be worth taking it apart for a look. At the end of the day it's just an electric pump and simple control board.

 

[youngblood]

I wish my w210had this option.

 

[jonnyboy]

i have a pump which i replaced with a s/h one. if you want to look at it and repair at leisure you can have it for the postage