AC controls/windshield wipers issue

[77S30]

I started with this issue on my introduction post but I think it deserves its own topic as this is very strange. The "issue" When I have the car started or over to ON, the AC/heater control panel lights up with the green LED's and I can select foot, vent, def ect. But as soon as I either turn the AC on OR turn the windshield wipers on the green selector lights go out and there is no more power to the heater control unit. If I put the wiper selector on intermittent 2 relays buzz...
Steps I have taken so far troubleshooting... Replaced the heater control unit= no change, replaced every relay that is with the AC and wipers= no change, Even the green box on the drivers side fender well by the firewall. After further investigation I found someone Past owner ran a hot lead from the battery to the windshield wiper motor's Red wire. I assume this giving power to the wipers.If I hook them up like its supposed to be, I get no power to the wipers or the heater control unit. Soo What I am thinking is, there is a amplifier or relay somewhere that isn't working and feeds both the wipers and AC control unit? Only thing is I don't know where it is. I did find a silver box on the passenger side foot well behind the ECU. You guys think this could be the problem? or maybe a ECU problem? There is quite a bit of sand in the corner and sand in that silver box.. I will update this with some pics tonight. Thanks for any help with this. I really want the AC and wipers to work!...

[77S30]

I have searched and searched and only found a few threds similar to my issue.. So no one has had this problem before? I will continue on looking over the wiring diagram and replacing parts as I can. I hope it is just a relay or something simple like that.

[biggie]

Never heard of that same problem before. Has to be some kind of short or something. I'd replace the HVAS controller first, then look at wiring behind it.