A/C Diagnosis.....

[Beebe]

So here's what I have tested and tried to eliminate being faulty.

Checked the A/C relay - Good
Checked the A/C fuse - Good
Checked voltage at high and low pressure switch plugs - Both Good , both showing 12+ Volts

I have hard Jumped the relay connection in the fuse box to the compressor and the compressor kicks in fine and blows cold air. So the compressor is good and the wires to the compressor are good.

I Jumped the High and Low Pressure Switches at the plug harness to eliminate the chance of a bad pressure switch.

SO.... I guess I'm down to a bad dash switch or the wires going from the dash switch to the relay fuse box ?!?!?

Here's the kicker... Sometimes when it's cool enough outside the A/C will turn on and work for me both with the A/C button and with the Windshield defrost mode......

WHAT GIVES? Driving me bonkers!

 

[Frank Enstein]

I know you jumpered the switches but put some a/c gauges on it to see where the pressures are. If the pressures are too high it can fail and you might be hurt.

 

[Erik the Awful]

Without having added refrigerant, I wouldn't suspect it of having too high a pressure. Since it kicks on when cold sometimes, I wouldn't suspect too low a pressure. I'd suspect the cold solders in the control unit, but you say the relay and fuse work fine.

How did you check the relay and fuse? Did you turn the system on and they got power, or did you jumper power to them and they worked correctly?