I have a problem with my a/c system on my 1992 Chevrolet Blazer Fullsize K1500 4x4. The electric clutch on my a/c compressor will not kick in when I turn on the a/c. I have to manully kick it in and it works and blows cold for a short period of time then the clutch kicks out again and the a/c stops working. I have checked the refrigerant level and its full. Ya'll got any ideas on what I can do to fix it?

 

first off, how do you manually kick it in? but i would check the two wires going to the clutch for power and ground, if no power and ground then i would lean towards a pressure switch problem. your truck also has a a/c controller module so i would also test powers and grounds to that also. heres a wiring diagram....

http://img707.imageshack.us/img707/6392/78362447.jpg

 

Check your pressure cycling switch - it's the switch on the accumulator.

Mine just went bad and we had to jump the wiring harness to make it run all the time (but I have to worry about icing up the system) until the replacement parts come in.

 

Probably just a bit low on freon. Mine was doing this very thing until I added a bit. Its actually normal operation of the pressure switch to keep the compressor off if there is not enough freon to keep it cold. Just be careful about mixing freon types (I just spent almost $1000 because I didn't do a full retrofit to 134a, just added it to the r12 oil). Hopefully, you've already changed over.