Sorry for the slow response...
They called Friday while I was in class and left a voicemail saying they found nothing wrong and to come pick it up. When I went in that afternoon, I talked with Chris and he said they found no codes or recalls and the test ride checked out OK.
There's only 5 turns between the dealer and my apartment and the DPS failed somewhere after the second turn.
I recall several people, including Chris, telling me some DPS problems were related to a bad ground. I had been having a "low battery" warning at idle for a few months and had been ignoring it. I read several threads here about how the stock battery was crap and wasn't designed to be laid on its side. I had planned to buy a replacement, but didn't have the money.
Thinking about the two issues, I put two and two together and hoped they added up to four. I got out the toolkit and tore off all the plastic. I then proceeded to disconnect, clean, and reconnect every connector and screw that I could find in the electrical system.
Since I had the afternoon off, I decided to go to St. Augustine, Florida for the weekend. I'm happy to say the DPS worked the entire time and I didn't see any low battery warnings.
Only time will tell if this is a permanent fix.