what wmtire posted, is probably the problem, since you swapped batteries.
usually, this happens when someone crosses the battery wires, tripping this resettable breaker/fuse.
make sure you've hooked up the battery wires correctly. don't go by color, go by where the wires go. the negative will ground to the frame.
and Zoe the Wonder Dog(R.I.P.)
'07 Roo 23SS pushing an '07 Chevy Avalanche
Equalizer WDH and Prodigy BC