"Joe Bobst" wrote in message
...
why is the black from
the second cable wired to the same nut (nut connects the black from second
cable, white from first cable, and the lead from dimmer) and why is the
white capped off?


Might have been part of a now defunct 3-way switch set up. I'd disconnect
the
second cable entirely and see if everything works. Standard admonishments
apply
here when working on your own electrical system. Good luck.

Joe

thanks Joe!