ac system question

[K3vdaw6]

hello.
I bought my 89 a few months ago. been doing little things here and there, ie. ks rewire, plugs, eng oil trans and diff fluid change etc. its getting hot out and my ac doesn't work. when I bought the car the previous owner said the ac didn't work and he wasn't sure why. he owned it for about a year. when I was in doing the plugs I noticed that the ac belt was off the compressor. a few days later I found the belt under the rear hatch in the drivers side compartment.
Im wondering if theres anything I should check before I try the ac. I think its been off for at least a year. I haven't had a chance to check and see if the compressor is still wired or if all the lines are still in place.
Im going to put the belt back on and see what happens just wondering if theres anything that could harm my car if the system f***s off on me

 

[jetjock]

AC not working could mean several things. Problems with the clutch not energizing, problems with the refrigeration system, or problems with the dampers for example. Quick check of the clutch circuit is to just turn the key on (no need for starting the engine) and light up the AC button. The clutch should energize.

Turn the energized compressor by hand because if it has gone tango uniform the system will require an overhaul. Past that the best thing is to put gages on the system after checking all the parts and hoses are present. Then inspect the belt. Turn it inside out and while flexing it look for cracks. If any are found put a new one on and go from there.

If problems are found with refrigeration (leaks, low charge, etc) fix those next. Since you're in the Great White North where R12 is verboten I'm assuming the car has been converted to something else. You'll need to verify that.

You can then check system performance and operation of the dampers. Keep in mind AC work requires specialized tools and knowledge. If you possess neither you must acquire them or find (even pay) someone who does. Or sweat...

 

[K3vdaw6]

So i did what u said. Pressed the ac button with the motor off. I could hear the click under the hood. Turned the compressor, not seized. But the clutch wont energize. Anyway to fix that or do i need a new compressor?

 

[jetjock]

Well, if the clutch isn't being energized what exactly is clicking? The only other thing that would click is the clutch relay under the battery tray and if that's the case the problem may be as simple as a broken relay or wire. On the other hand the clutch magnet coil could be open circuited. Use an ohmmeter to check it. You can't tell if the compressor is seized with the clutch not working unless you turn the compressor portion of the assembly. Otherwise all you're checking is the clutch bearing. Identify the clicking source first though

 

[K3vdaw6]

How do i check the clutch magnet circuit? I have a decent multimeter just not sure how to do it and what im lookin for

 

[K3vdaw6]

The clicking is coming from the front drivers side of the car. Cant see the source but it could be conin from under the battery tray

 

[jetjock]

Check the 10 amp AC fuse in the pax side kick panel first:

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=22

If that's ok you're likely low on refrigerant.

Edit: Actually, now that I look at the schematic, if the relay under the battery tray is clicking that fuse is good since it powers the AC amplifier. I'll say it again: identify the source of the clicking.