Civil Nav Troubleshooting Options

[AstroDan]

Hello. New here, great site. Please forgive me if this info I'm requesting is on here and I haven't searched properly to locate it. If so, please point me to it and I'll abandon this post...

I'm working on Blackhawks here in Germany (alpha models) and am looking for some trouble shooting sources other than the TM's provided for pretty much anything civil nav related - in particular the VSI and anything it is electrically tied into. Every day we have some kind of flag issue and the wiring diagrams are a help but not a lot of us know about the UNS or GPS. I don't need to know how to program coordinates, but I would like to know how to work these enough to simulate a ground MOC. Just a simple tutorial site for UNS/GPS and how it affects the respective displays.

Thank you!