Thank you both for your replies.  I haven't yet checked it with my DC controller, I have to fish it out.  I did program one of my other Locos to address 3 and I was able to get it to switch to 3 and back.  Taking it to my local hobby shop seems like a great idea.  I'm fairly confident that the loco works, the dealer I bought it from is very reputable.  Thanks again.

I purchased a used Spectrum PRR K4 on e-Bay and just received it (its beautiful btw).  The problem is, I can't get it to run on my track.  I'm use Bachmann's EZ-Command, which has been flawless.  The seller said that the short address was 3, but when I tried it, it wouldn't work.  I tried all the other addresses as well and none of them would move the loco.  I was able to run all my other locos with no problem so it isn't my DCC system.  The wiring seems fine, and the connections were snapped tight.

My questions are: 1) Could anyone suggest some things I could do to try to trouble shoot the potential problem? & 2) Since it was purchased used, is the warranty still good?

I contacted the Seller and he said they use NCE equipment and it ran well for them on it.  I can't imagine that a Bachmann loco wouldn't run on a Bachmann system but would on another system (I have 7 other bachmann locos that run on my dcc system without difficulty).

The Loco is Item #84101, but it didn't come with any paperwork inside.  Is there a way that I can download the paperwork for this item?