I've got a 2004 r-12x and f-12x. The other day I tried to start the r12 and the battery was dead. I really wanted to go out so I tried starting the f12 and it started fine. I swapped the battery from the f12 to the r12 in hopes of a quick fix and charge the dead battery later. I try starting it, it sounds like it has a good charge, but it never fires up. On the third attempt to start it, the battery light starts flashing/beeping. I took the battery out, put it back in the f12 and it started just fine. I charged the dead battery overnight, hooked it back up the next day. Once again sounds like it has a good charge, its trying to start, but it never fires up. I did not get any battery warning this time. Has anyone had this problem and/or knows what is wrong?