I did a search and didn't come up with anything. My compressor doesn't come on when I turn on a/c...or on max. Checked with a meter and voltage doesn't seem to change on connector. Could it be that it won't turn on cause the refrigerant is low? Don't want to short anything out messing with it before I get some advice from you guys. It does have 134a in it. Any help would be appreciated.

Mike

 

I do belive there is a pressure switch the blower motor, have you checked any of your fuses to see if any are blown

 

also check the connection on the compressor , might have corrosion at contacts

 

if you have a low refrigerant charge, your low pressure switch will prevent power from going to the ac clutch. bypassing the low pressure switch for a second should engage the clutch. if it does, you need a recharge of refrigerant

 

tjc has the right idea.
I just converted my system from R12 and had to hot wire the clutch til I got enough 134 in er for it to kick on its own. Just run some alligator clips from the battery posts.

 

dieseldan7.3, how was the conversion to 134. did you have to change any components? My 93 - I think is finally lost enough r12 over the years because it isn't getting very cold like it used to. R12 too expensive IF you can find it.

 

Big red....... make sure the blend doors are closing fully this is a known problem with the later years 93-94. There is an adjustment point behind the glove box, a white locking devise and a red barrel. It's a but tough with big fingers but you gently but firmly pull the top of the locking devise enough to allow the red barrel to move 1-2 notches.......sorry can't remember which way. The locking devise must be locked onto one of the notches or the doorwill not work. If you rotate the heater dial to closed you can determine which way for more pressure.

 

Hi guys,

So to check the compressor, I need to run 12V to one contact, and ground
to the other - is that right? Does it matter which way around?

Thanks,
Chris.

 

nope. start motor, turn the ac on, take the connector off the low presure switch,(it on the can looking thing on the passenger side), and with a piece of wire or paper clip or something like that, jump the two connectors in the plug. if the clutch engages and the compressor turns, you need a recharge. if the clutch does not engage, your problem is in the switching sircuits.

 

I picked up a conversion kit at Advance Auto for 40$ and couldnt pass it up. Very cheap considering it would cost about 340$ at a shop to convert it.

The kit includes:
3 big cans of R134 and oil
1 hose with inline pressure gauge and coupler
2 new style quick coupler ends that just thread on to old ones
2 new caps
1 set of destructions and an informational DVD if you cant read.

The 3 cans filled up my system which I believe had been drained empty over the years. I had another can which I used to top off the system.
I changed out no components and was lucky I didnt even have to drain the system.
The air conditioning freezes you out at 85F and it kept up great even at 98F last week.

Dont forget to hold the can upside down when filling. I found that out the time consuming way.
My floor vent wouldnt shut all the way so I had to tiestrap the arm shut to get air out of the dash vents. Bad solenoid or something I guess.

 

dan, if your floor vent will not shut to divert air up to the dash, check the little 1/16 vacuume hose that goes from the tree to the heater box.

 

I will try that. I remember seeing a small hose under there now that I think about it. I just assumed the vacuum cylinder thing was bad.
What is the "tree" you are talking about? Its kind of hard to see all the stuff in the dash w/ out taking the control panel out for the heat and air.