After a few days of cutting, drilling, etc on my fairly recently acquired Williams/Samhongsa USRA 4-6-2 I was at the point that I needed to install the PS2 kit I got from MB Klein.
It took me a while to install all the parts, I just took my time doing it, no rush. I placed the engine on a piece of track and powered up my Z750 for the smoke test and everything worked fine.
So the next step was to load the sound file I had chosen, one of the NYC USRA Pacifics.
I was going to use my laptop, thinking that it would be easier than lugging all the stuff (TIU, PH-180, handheld, cords, and of course engine) downstairs to my PC, but being I don't have a permanent test bench with a piece of track setup it wouldn't have saved me any time, so I lugged it all downstairs just like in the past.
Download was a piece-o-cake, took 6 minutes and engine responded fine. So I unplug everything and lug it back upstairs to see how the engine will run on the layout. Easy enough.
Placed the engine on the layout and turned power on the the power strip for the TIU, PH-180, and Command Base-1L...Handheld sez, NO ENGINE FOUND!?!?!?! WHAT? WHY does this ALWAYS happen?!?!?!
So I fooled with the engine a bit and after about 3-4 aborted attempts I sez, "Try an older engine to see if it gets detected". NOTHING!!!
That's when it hit me, YA GOT TO TURN THE PH-180 BACK ON YOU KNUCKLEHEAD 
I bet I've done this on 5-6 PS2 upgrades, when will I ever learn 
Good thing I caught my error, I was getting ready to post my "problem", I'm sure you guys would have had a good time with it 
Maybe a permanent test bench will be in my future plans!
