theman4444

NEWB HERE...

I know that there is a specific thread for this subject but no one can answer my question.

I'm not getting 12v to the compressor and I just stuck the wire from the battery onto the compressor lead and the clutch kicked in and it started moving! I left it on there a little longer than 30 secs just to see if it would work and I'm pretty sure it was blowing colder air. I didn't want to fry the system so I took it off again, but now I don't know why it isn't getting enough juice to start it. I hooked the voltmeter on the original lead going to the compressor and it only had 0.6v going to it when the A/C switch was ON, and like 0.2v when it was OFF. I don't think that a fuse is blown because I'm getting a reading at all. I checked the refrigerant pressure and it seems to be within the proper working range. SO WHAT'S WRONG WITH THE SYSTEM!!! My friend who sold me it says it might be the logicon a/c control but I'm a crappy electrician so I can't trace it very well. Help please.

J-Rat

iTrader: (2)

YOUR SYSTEM IS LOW ON REFRIGERANT!!!!!!!!!

theman4444

I checked the levels and I added some to it and it never kicked in the whole time. I checked it again and I accidentally added too much so I took some out and it still didn't kick in. I'm sorry to disagree but I don't believe this could be the answer. OMI I think it's a bad wire somewhere but let me hear some more opinions.

J-Rat

iTrader: (2)

What method did you use to check it. What were the pressures on the low side?

Turbonut

iTrader: (1)

Gotta put gauges on there to see pressures, or at very least, what does the sight glass indicate?

theman4444

I bought a Interdynamics charging and measuring kit from wally world that we used on all the rest of our cars and it worked fine for them so I'm pretty sure it's accurate. I over filled into the red which was about 75psi (on the low side) but then backed it down into the blue section which was about 43psi. It should've at least kicked in then since it was in working pressures, right?

tmking66

I had the same problem with a system in my 85. The problem was that no current was getting to the compressor to kick it in when the ac switch was turned on. Probably a problem in the logicon. I really did not want to tear into that thins so my resolution was to run a wire from the compressor to a new switch that I mounted on the lower dash just left of the wheel and ran a wire from this to a wire that is hot when the ignition is on. I used I think a 20 amp fuse in the new circuit. Check your ac fuse in the fuse box and use the same size fuse in the new circuit. To operate the ac now all I have to do is turn on the fan and hit the new switch for the compressor and the ac is on. I did this last spring and it is working just fine today.

theman4444

hmm... It sounds like a good fix, but I want to stay as stock as possible with the little things like a/c. I don't want to bypass any switches that were meant to be there in the first place for a quick fix. What is the logicon anyway? Is it the main box in the dash that controls the heat and a/c?

HAILERS

The car has a DRIER. The drier has a PRESSURE SWITCH. The pressure switch has two wires going to it. DISCONNECT THE TWO WIRES.

JUMPER THE TWO WIRES. TURN THE A/C TO ON IN A NORMAL FASHION.

IF THE COMPRESSOR ENGAGED YOU EITHER HAVE LOW PRESSURE OR THE SWITCH IS FUNKED UP.

THE DRIER IS IN FRONT OF THE CAR NEAR THE WATER OVERFLOW TANK.

TWO WIRES. JUMPER THEM.

IF THAT DOES NOT MAKE THE COMPRESSOR ENGAGE, SEE IF THERE IS 12VOLTS PRESENT ON ONE OF THE WIRES.

THE OUTPUT WIRE GOES TO THE A/C RELAY ON THE LEFT FRONT OF THE CAR IN THE SAME GENERAL AREA THAT THE OVERFLOW BOTTLE AND THE DRIER ARE LOCATED. JUST TO THE LEFT SIDE.

theman4444

Dang man, why is everyone yelling at me... ALL CAPS OR NOTHING AT ALL!! HAHAHAHA. So I have to go to work now but I will try the drier thing when I get back. Thanks for the ideas guys. I really need the cold air. Screw top speed when you get heat stroke everytime you drive your car. I only race at night anyway.