At first it does sound like a dead battery issue, but if you have checked the battery voltage and it is good, then it may be more than just that. Even if you charged it, check to see if it is at least 10 volts. Other than that it could be a loose door, that doesn't push the battery in. I know a while back, the prongs that the battery hits, bend in and lose contact with the battery. On the DFX I have used a hook to pull them forward a bit and cleaned up the contacts on the battery pack and it fired up for me. Let us know if you get it going.