a/c problems

[lazyjoe]

My neighbor just bought a 91, D250. The a/c worked when he got it. Then it quit. He noticed a little black box on the side of the expansion valve, tapped on it, and it started working. Now it's quit again, and tapping does'nt work. I guess I'v never seen one of these black boxes. My 93 does'nt have it. What is it? Could this be the problem? And can these still be bought? Thanks, Joe And unrelated to this. But how do you post pics on here? I know I'm a computer dummy. But I didn't think I was this bad. But I can't figure it out.

[PToombs]

Can't help ya on the A/C, but on the pics, you host them from Photobucket. Just start an album, then click on the last line under the picture. Come over here, and right click, then left click on "paste".
Usually looks better if you hit "Enter", to drop down a line after you type something, then right click.

[nooblet]

That little black box is a temperature sensor. It has a probe that slides into a little sleeve in your low pressure line. You can buy one from dodge for like $80, or you can take a relay and wire it to be hot when you turn on your a/c... thats what i did.

The switch turns your compressor off when your a/c gets too cold. If you wire it with a relay you are bypassing that feature, so the compressor will never disengage unless you manually shut it off.

If he is running R12 and he did this it will turn his a/c system into an ice block if you don't watch it. Running r134 its impossible to freeze it up though. Mine runs full blast for hours and never freezes (did i mention i hate r134?).

I hope that helps!

Chris

[nooblet]

oops i just realized this was two weeks old

[lazyjoe]

Don't apologize, he still had'nt figured it out. I will tell him. Thanks nooblet .

[nooblet]

Ya, any time. If he wants to know how to wire it with a relay let me know. I think i still have the makeshift wiring diagram i found. Its really pretty simple and it works great. The guy who made it said those factory sensors use a really cheap relay in them, which is why they break pretty often. If you wire it with a quality relay (bosch) it will go a lot longer.

Chris