Mercedes-Benz Forum banner

1 - 9 of 9 Posts

·
Registered
1984 300D
Joined
·
11 Posts
Discussion Starter #1
Recently purchased 1985 300D and everything seems to be working pretty well except not too sure about climate control. If you switch unit from OFF to "E" position, fan will not start. All other modes seem to work fine and fan runs in HI/LOW and cycles up and down correctly in Auto. If the fan is already running in another mode except "E", if you then switch it to "E" it runs OK (HI/LOW/Auto) I have ordered but am still waiting for my service manual from MB. The owners manual describes the system but not in the greatest detail. It seems that the fan should work in the "E" mode anytime, Is that correct? If my system has an issue, what component should I be looking for? (bad switch, etc?)

Thanks, Steve
 

·
Registered
1985 California 300 D Turbo Diesel and '85 Federal 300D Turbo Diesel. '84 Cali 300D - SOLD
Joined
·
360 Posts
Sorry, I don't know how these are supposed to work either. I was wondering what part of VA you're in.
 

·
Registered
2013 MINI Copper S Clubman, '84 300CD-weekend car
Joined
·
10,152 Posts
On earlier models, there isn't an "E" button, but we have an "EC" button and the fan should work with that button pressed first.
 

·
Registered
1984 300D
Joined
·
11 Posts
Discussion Starter #4
Sorry, I don't know how these are supposed to work either. I was wondering what part of VA you're in.
Fairfax VA. It's really the "EC" button not "E" like I earlier thought. I did read somewhere a detailed description of what vents are supposed to be in operation depending on mode but it did not discuss blower speeds, etc.
 

·
Registered
1984 300D
Joined
·
11 Posts
Discussion Starter #5
On earlier models, there isn't an "E" button, but we have an "EC" button and the fan should work with that button pressed first.
You are right, it is the "EC" button. Not sure why blower does not come on unless I cycle through another mode first. Perhaps mode switches dirty? Car has about 174K well maintained and super clean interior.
 

·
Registered
2013 MINI Copper S Clubman, '84 300CD-weekend car
Joined
·
10,152 Posts
It's possibly the unit itself suffering cold solder joints, it won't get better, but if it doesn't worse and you can live with it, no need to do anything.
 

·
Registered
1996 E320, 2005 Toyota Camry
Joined
·
1,810 Posts
fan

If you can make it work by cycling and the problem doesn't get worse, leave it alone (especially if you have to pay someone else to fix it).
Hemersam
 

·
Registered
1984 300D
Joined
·
11 Posts
Discussion Starter #8
It's possibly the unit itself suffering cold solder joints, it won't get better, but if it doesn't worse and you can live with it, no need to do anything.
Good point on the Cold Solder Joint. The old Becker Radio had one. I was able to isolate and repair it, but I got lucky because it was staring right at me when I removed the cover. I'll probably let the Climate control Be unless it gets worse. Steve
 

·
Registered
1984 300D
Joined
·
11 Posts
Discussion Starter #9
If you can make it work by cycling and the problem doesn't get worse, leave it alone (especially if you have to pay someone else to fix it).
Hemersam
I'll leave it as suggested unless it gets worse. The car is in really nice shape and the previous owner maintained it well and included all records including original invoice. If it quits or gets worse, I'll probably order a reman switch assy and install it/Steve
 
1 - 9 of 9 Posts
Top