Was going through the little 93 wagon trying to figure out why the A/C wouldn't engage despite having sufficient freon in it - I found that when I jiggled the wires to the evaporation thermo switch (sensor that sits on top of the evaporator housing behind the glove box) the system magically came to life! It's got 3 wires attached, red/blk, brn/wht, and blk/red.
Now, I know you can easily bypass the thing and jumper some wires but I'd rather not. Trouble is, I can't find this part anywhere on the web. Anyone else ever hear of this issue? I've searched on this now all day long. Halp! Burning up in Indiana. lol.