My light on the on/off switch went out as I'm driving and, naturally the air quit. The compressor won't kick on. I changed the relay, but no help. Want some advice as to what to try next. Thanks for any help.

I would've tried to bypass the switch & relay first to ensure it's not a problem with the compressor. You've already eliminated the relay. Start simple. Check your ground connections. Then I'd try bypassing the switch itself. I wish you luck - AC compressors aint cheap.

Your probably low on freon, you have what is called a low pressure switch in the low side line, when the pressuer gets low it won't let the compressor come on therefore saving it from burning up. Have your pressure checked and add freon if necessary.

. I have the same problem you have. My problem is the ac compressor clutch coil is bad and it pops the a/c fuse that is located next to the heater relay under the passenger side dash . Check the resistance of the a/c coil . It should be 3 to 4 ohms, If not it is bad and Will pop the breaker. I have heard that there is no low pressure switch on a 94 pickup. Only a high pressure switch located at the evaporator. Has anyone changed the a/c coil on a 94 pickup?? Do you have to remove the compressor??

If you have no light at the a/c on button the fuse is blown. This fuse location was not in the manual that I had(Clymer) It was a bitch to find.