1998 aurora drivers seat

My wife has a 98 aurora the drivers seat does'nt do any functions except for the lumbar. The side mirrors do not work either.The motors work ok when I bypass the switches, and the seat will move around. The switches in the door panel check out ok. So is it the black box under the seat? Is this called a control modual? Where do I get one and how much will it cost me?
Also where can I get free wiring diagrams for this? PLEASE HELP!

go to alldata.com it costs 25$ FOR ONE CAR I THINK BUT, IF YOU DONT HAVE ACCESS TO WIRE SCHEMATICS ITS YOUR BEST BET. ALL THE INFO U NEED FOR YOUR CAR

thanks for offering your help

You'll find that it is the usual broken thin wires in the door jamb. I have it too. For me it started with the lumbar and power doorlock switches and just recently the seat adjustments. I am too lazy to fight with the dust boot and wrapped wires to find where the breaks are so I will farm it out as soon as I find a decent electrical place.
Jay