2003 360 "transmission error" light

I backed my newly acquired 2003 360 out of the garage into the driveway for a wash, and when I attempted to start it again afterwards, I'm getting a "transmission error" light. Any suggestions? It has about 6000 miles on it.

The full course of events:
1) started it in garage, backed it out onto the driveway.....only ran it for about 8 minutes (possibly my first mistake)
2) after 45 minutes or so, attempted to restart; at this point it turned over a few times but didn't catch, and the "transmission error" light came on. After this it would not turn over.

Here's what I'm trying right now:
1) unplugging the battery for 5 minutes and re-connecting (to clear the error?)
2) trickle charging the battery overnight (could low battery cause this?)

Thanks for any assistance.

 

Rifledriver: Many thanks for the quick response. You caught me in time, so I will not disconnect the battery. I'm going to trickle charge and check all fluid levels while I figure out how to get it to a repair center :-(