Join Date: Apr 2007
Location: Alpharetta, GA, USA
I've got the same 550 mounted on my 07 GT using the same power feed. I've seen the "resume on battery" prompt only once when I first installed it. Since then I never paid it much attention. I've had it shut down by itself during long gas stops, so I know it doesn't stay on longer than 15 mins or so. On the other hand I wasn't sitting there watching it so I don't know if the resume prompt came on or if it just turned off. Aside from that, I usually turn mine off manually if I'm walking away from the bike to avoid tempting looky-loos to mess with it. I've never had the Zumo turn itself on except when starting the bike.
I haven't had any software upgrade on the bike since I picked it up Oct 06; however, that may happen when I go in for service on Friday. I did update the Zumo a couple of weeks ago - after having it a little over a month there had already been two minor updates.