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Another newbe here. Have looked through many of the door assist threads but did not find one that answers my issue. All of the doors and trunk asists work except the drivers door. One person said if you close the door too hard it can mess it up and that you then need to reset it. Truth or fiction or what may be the issue? Great site for helping.
Second question, almost afraid to ask this one. The light behind the digital temp readout on the console is out on the driver side. Is there a way to replace this bulb? Many thanks
Gary
 

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1. if the door close assist system 'times out' too many times (i forget how many times it needs to happen), then yes, the system turns off and needs to be reset. a 'time out' is when the system is trying to suck a door closed, but that it senses that it is unable to. this can be caused by a leak, though, not necessarily by one. the way to reset the system is, either to unplug the battery, pull a fuse, or disconnect the system (behind the paneling of the trunk - next to the gas tank). though, keep in mind that if all other doors continue to pull closed, then the system has not timed out and there is an issue with the door / line running to the door that does not work.

2. yes, the bulb is easily replaced. this may sound scary, but you need to pull the 'auto' button straight out. it sort of pops out and back in w/ a catch. i forget what i used to pop it out, i think maybe a thin knife. but whatever you do - be careful not to break the button or the wood. behind the button is a bulb that you will need a tweezers to pull straight out. replace, and you’re done.
 

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sorry, but i am not sure which fuse it is. i know that i have pulled the fuse to reset mine, but i do not know which fuse off the top of my head. basically, pulling fuses does not harm your car. there have been times that my car has acted up and i pulled every single one (at both boxes - under the hood and in the trunk area) one at a time, turned my car back on, and issue resolved! sounds funny, but these cars have a lot of electronics involved. much like reseting a computer - first thing you do when you run into an issue is - reboot! at each of the fuse boxes there is a card that shows which fuse does what though. if you pull all - only thing you might need to do is have your radio code handy, and reset your memory seat positions :). good luck.
 

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Yes it is Fuse #9, located in the fuse box in the trunk.

This will reset the pump.

When the pump has timed out; no assist anywhere will work.

If the assit continues to work on all doors and trunk except the drivers door - you have a different problem: The pump is fine; the problem could be the connectors at the pump for drivers door, a problem in the line from the pump to the drivers dooor, or a problem in the drivers door itself.

I was resetting my pump at least once weekly, until I took it out and adjusted it according to a great thread on how to do this. It has worked flawlessly now for 8 months.


Hope this helps.

Ed in SC
 

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Assist Time-Outs - Only One at a Time

The close assist time-out (I believe it has to happen twice) will only disable close assist on the door/trunk that times out. The others will continue to work as long as they do not also time-out. Resetting (pulling fuse #9) will clear the time-out faults although they will typically re-occur.

I have had sequentially failing doors at high altitude (Lake Tahoe) which were completely resolved when I pulled the fuse back at "sea-level" (Sacramento, CA). I'm sure that the pressure switch adjustment is needed but they have been working fine for months.

The penultimate reference on the close-assist operation and diagnostics is located at V12 Uber Alles, Getting to know your Closing Assist Pump in a W140 Mercedes Benz, an article by Brett Allison. Very interesting and worthwhile reading.
 

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Each vacuum/pressure circuit has its own timeout, two unsucessful attempts and it disables that door or trunk circuit, there is a lot of good info, but some of it is defective, read the "V12 uber alles" article it is the best published info available.
 

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i must politely disagree and say that when my system timed out w/r/t/ one door (drivers door), the entire system went and no longer pulled the remaining doors closed. so, to me, this meant that the system times out as a whole. though, when i took the unit apart, i remember there being sepearate lines running into the system - this does not mean that there are sepearate circuits for each door.
 

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i must politely disagree and say that when my system timed out w/r/t/ one door (drivers door), the entire system went and no longer pulled the remaining doors closed. so, to me, this meant that the system times out as a whole. though, when i took the unit apart, i remember there being sepearate lines running into the system - this does not mean that there are sepearate circuits for each door.
I'm not saying that you are wrong with what you observed, but you are the first person I have seen to have observed this. Universally, people have found that one door at a time experiences failure to function due to the pump timing out on just that one door.

There is the question of what happens if multiple doors were closed simultaneously, and then the pump times out while operating more than one door. I have no idea of the consequences in that case. Will it shut down only one of the door lines (maybe the first one closed) or all of them after timing out twice? I don't know. I have never pulled my pump back out to investigate this because I haven't had to... My pump has operated flawlessly for almost 4 years since performing the adjustment of the pressure shut-off switch.

Brett
 

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The close assist time-out (I believe it has to happen twice) will only disable close assist on the door/trunk that times out. The others will continue to work as long as they do not also time-out. Resetting (pulling fuse #9) will clear the time-out faults although they will typically re-occur.

I have had sequentially failing doors at high altitude (Lake Tahoe) which were completely resolved when I pulled the fuse back at "sea-level" (Sacramento, CA). I'm sure that the pressure switch adjustment is needed but they have been working fine for months.
Thanks for reminding me. I should drop a note to Pete to add this info the the article. I never did so after our conversations.

Brett
 

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will closing the door like any other car damage the system.
does it sense that the door is closed and over rides the close assist?
 

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I thought the pump sequences, I think i have heard it exercise more than once when multiple doors have been closed.
You have to remember the door sees a closure, it sends pressue down the line to activate the diaphram, it confirms closure thru the micoswitch or times out. It then cleanses the system with vacuum to reset the diaphram for the next action.
 
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