circuit boards

I just recently started having problems with the car turning over and getting the "unknown driver" on the display. lights on the dash come on and the air turns on as well. The air shuts off when I attempt to start the car. I did some looking around the car after getting frustrated and I found...

Here's one for you: I have had a drain on my 2004 Trailblazer battery for the last year and finally figured it out this past Saturday!!! (no extra cash to take it somewhere) So I have had a 6.4 amp draw on my battery and replaced the battery once. Everything tests fine (battery, alt, etc) yet...