Just a little footnote, i had the same problem with my 85 500 sec, the blower worked but the a/c did not. I ernt through all kinds of things, wiring, compressor, etc., to find out that it was the ignition switch, which is actually a common problem with the 126. I dont know what the wiring setup is for the switch, but for some reason the a/c compressor is connected to it in some way, probably through some relay. With a little jiggle of the key back and forth the compressor would kick on and off. Dont know if this helps, but there are many threads in here about the 126 ignition switches.