Hello Josh,
The Bk/W wire should produce 12V when the IGN is on and the kill switch is set to RUN. If it does not, then you have a problem.
The GPS splice on the MC18 isn't the same as the MC21... it's doesn't have one!
Full colour wiring diagrams for every model are completed, and will be available in the new Members area when it opens.
_________________
Andy.
NSR-WORLD.COM
Please keep all responses to Forum posts on the Forum so that others may benefit.
Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.
Check us out on Facebook! Please "like" our page!