I found a site that lists all the GM service bulletins for 2003 H2's.
http://www.lemonfree.com/more_detail...d=1658&yr=2003
There is a bullentin listed that mentions the exact problems you are having. Something about reprogramming a module in the driver's door, if I remember correctly. Sounds like this is a common problem, am surprised it hasn't happened to my H2, though who knows? Perhaps this is why it is in the shop again right now.