Ken,

I basically had the same problem as you. My fuse #12 kept blowing when I was running the AC. I had thought it was because of the compressor going bad. But it turns out that there was a bare wire causing a short. The wire was the green wire going from the compressor to the dryer. If you look underneath the driver's side head light, there should be a bundle of wires going through the radiator support. There's a rubber grommet there that had come off. The wire actually ran from the compressor, along the fender, underneath the battery tray, through the radiator support, across the front side of the radiator to the dryer. My car is also a 1990 but it's a sedan. I would assume that it's pretty similar to your wagon. You might want to check out that wire. I wrapped some electrical tape around the wire and my AC has been running fine since. It needs recharged, but it runs....

Matt

If a fuse keeps blowing it's not a good idea to replace it with a higher rated one - fuses protect the wiring from excessive current and are rated according to the capacity of the wiring they protect.

General deterioration of the wiring harness affects earlier cars to yours so it's less likely to be the cause of your problem.

Check this thread:

http://www.brickboard.com/RWD/index.htm?id=976992&show_all=1

It's possible the over rated fuses have caused the insulation to melt somewhere in the wiring harness - you'll need to get a multimeter and test the circuits for short circuits.

Straightaway, it's a short! I have a 85 B21FT engine and the wiring harness, plus firewall wiring, is known for crumbling over a period of time so when I went to install the engine in this guy I was busy repairing wire FIRST. The same thing happened on my motorcycle that kept blowing my ignition fuse and the bike would just SHUT DOWN while I was riding it. I whipped out the soldering gun on that one and never had a problem again.

So, that being said, start to go over all of your wiring. This mechanic might have ignored stuff like this and I have a tendency not to trust anyone that doesn't have a vested interest in my ride since being a female makes me a bigger target and I have had some fights with a few assholes that told me my business. I bought a complete wiring harness from the dealership (and a few extras) which put me back $1,000. I got the car home and had the exact same problem until I went over it myself. It was easier for them to tell me to buy another car and this really chapped my buttocks. Never again!

Chances are the wires coming from your ECU to the compressor are grounding out, which might be why some of your other components are going nuts back to the fuse box so start there. If the A/C doesn't work, then disconnect the electrical wiring anyway, but take care of the wires before you do.

If you do all of this and your window still acts crackhead, then take off the interior panel and test the wiring there. Those switches are so easy to rebuild with a simple $3.00 tube of die-electric grease so you might want to do that while you are there and get more power to your rollup.

Charlane