Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

LinkBack Thread Tools Display Modes
Old 11-20-2002, 08:45 AM
Coming back from burnout
Join Date: Jun 1999
Location: in the Pacific Northwest
Posts: 2,274
Restoring 240D--Trying to fix Vacuum Circuits for Door and Trunk Locks

I am restoring a 240 D and presntly my vacuum circuits for my Door Locks and Trunk Lock dont work correctly.

What I need most is a diagram of the system, I cant find one. I checked the Service CD and there isnt much.

Does anyone have any advice as to the key failure areas, troubleshooting advice, or documentaion such as diagrams?


Reply With Quote
Old 11-21-2002, 04:27 AM
Registered User
Join Date: Oct 2002
Location: Toronto, Canada
Posts: 700
I fixed my door locks without any diagrams. Turned out to be one of the pipes fell out of it's rubber sleeve, but I could hear the pump working, not sure if this helps, but the system is not very complicated, just make sure the pump is engaged and there is no leaks in the system
Reply With Quote
Old 11-21-2002, 07:58 AM
Posts: n/a
The 123 car has no electric pump as do many other models. Start with a hand vacuum pump at the vacuum connections going through the firewall near the oil filter. See that it holds vacuum there. It probably will not. If not, split the circuit by starting at the passenger front door. At that diaphragm, remove the line that goes OUT of that diaphragm toward the back door and plug its connection on the diaphragm. If both front doors work well then the problem is in the right rear door, fuel door or trunk. If they still don't work then work your way back toward the firewall.

This is very simple troubleshooting and you start in the middle and work toward the problem.

Good luck,
Reply With Quote
Old 11-21-2002, 11:59 AM
Registered User
Join Date: Mar 2002
Location: S.F. Bay Area
Posts: 502
vaccuum problems


If you go to Ebay under mercedes parts you'll always find a guy advertising a boolet that he published on just how to trouble shoot the system on 123s. Try his website **************.com to order direct. Once you've read the booklet you'll never have trouble again.

The yellow and red tubing in doors is lock and the yellow and green is open. Logical when you think of it. The brown tube from inside the hood is ignition switch and the other color, green, I think, is the vacuum controls for the a/c and heating.

Start solving your problem by isolating all the systems but one. Then you'll know which system has the leak and can attack only that one. Obviously, the hardest system is a/c and heating because of it's location.

Good luck.


Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 03:34 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2023, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page