[onewhippedpuppy]

Originally Posted by dad911

Start at the panel, and make sure all circuits have power. As stated above, could be a bad leg supplying the panel. Use a 110/220 test light, one lead on common (where the white wires connect) and check the screw (output) of each breaker.

I've also seen breakers go bad, and even though on, there is no power out.

You need to start at the beginning.......

Me too. I've had multiple older breakers show good per the breaker position, but not actually pass current.

The only time I've ever experienced wires actually breaking without any other action is aluminum wiring that was not properly protected for corrosion breaking off at connections. But even then it did not fail within the wall because it was protected by the wire sheathing.