2007 GT 359XL Interior Lighting problem

[Trailboss1959]

Greetings all, I have been living in this since Aug 2013.. Wife bought it used while I was still deployed. Currently have a problem with the thinline 12V main cabin overhead lights. I have determined the switches are receiving voltage. Fuse and power board are good. However not getting voltage to the lights..
1. Can someone tell me what this bus bar is and what the voltage at each terminal is supposed to be? see the attachment.
2. Is there a wiring diagram for this 12V lighting somewhere I can download?
Thanks for any assistance.. will keep working it.
Trailboss

[tncruiser]

if you were to back wire 1 fixture iw would probably make them all all work ,start with a jumper to see if it works if so then concealing the wire will be your only problem
brianj