My dog chewed the brown wire from the a/c unit outside. The white wire and red wires were spliced. My wife then went outside and attempted to connect the white wire while the breaker was still on and now I have no power to the thermostate at all. I went to the garage and made sure the breaker was off, flipped the switch and nothing happened. I cut out the damaged part and reconnected the wires and cut the breaker back on and still nothing. Could something be burnt out?

It should have a low voltage fuse on the control board that protects the transformer. It should be just a simple 3 or 5 amp automotive fuse that needs to be replaced on the board.