Hi, newbie here. Bought a 2003 TT from a private party. It has a Norcold 510 frig, which I assume is a "3 way" since it has auto, a/c, and lp options. After reading countless threads about the pro's and con's of driving with the propane on, I'd rather not. Does the frig work off the battery while driving if it is set on auto? We haven't taken it more than a couple of hours away yet, but want to make sure we keep the frig cool on longer trips. Just trying to figure out how it all works. Thank you!