Vehicle: 1982 300SD

Problem: No A/C

SO FAR:

As of now I think that the system is 1.) empty of any freon. and 2.) I think the ACC (Air Conditioning Controller) is bad. Here's why:

With the car running and the A/C in normal mode (the middle of the 5 buttons) and the wheel all the way to cold, the compressor will not engage. When I jump the Low Pressure Switch on the Reciever/dryer the compressor engages. No cool air though.

I took off the cover beneath the glove box and found the plug to the blower motor. checked for voltage and came up nill. Now, it's very hit or miss, but sometimes playing with the buttons I can get voltage to the blower and it does run whenever the 12v is present, so I have ruled that out.

Also, whatever this thing is (pic #1) makes some springy clicking noises occasionally. This is also only when it is actually getting voltage across pins 8 and 12. It takes a lot of fiddling around with the ACC and even then if I switch buttons it may or may not stop blowing.

I think my next step is to replace the ACC. Hopefully, this will give me consistant voltage to that thing and in turn the blower.

Then I am going to figure out how to make and adapter and use nitrogen to test the system for leaks before filling it with freon and seeing if it actually does work.

Any hints or ideas about this would be really, really helpfull. Thanks!


PIC 1: Some sort of unit in the A/C system. Anyone know for sure?

PIC 2: The vacuum element for the center vents. I found that it was just dangling there un attached to anything and the lines all capped off. ordered a new one.

Attached Thumbnails

   

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1987 MB 190E 2.3 16V- Name Pending
1982 MB 300SD -Old Blue
1965 Ford Mustang - Laura

One issue at a time.

You're likely correct in that the system is low on freon. Did you put a set of gauges on it?

BTW, there is no component known as "ACC". I believe you are referring to the "CCU"........."climate control unit".

You are correct about the CCU. Got the names mixed up, I did.

No, no gauges. I don't have any as of this moment and when I went to the parts store today they were out due to the recent heat wave. Everyone has been scrambling to fix their A/C.

What should I be looking for when I do put the gauges on the system?

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1987 MB 190E 2.3 16V- Name Pending
1982 MB 300SD -Old Blue
1965 Ford Mustang - Laura

What fluid are you using?

The pressures depend on ambient temperature...........there's a chart for reference that some of the a/c fellows will have.

It still has the old style R-12 fittings on it, so I'm assuming that it is still using R-12.

__________________
1987 MB 190E 2.3 16V- Name Pending
1982 MB 300SD -Old Blue
1965 Ford Mustang - Laura

Find a local shop that still handles R-12..........they'll have the gauges and the fluid to fill it.