Scott, most of the time the switch you ask about is actually a set or relays controlled by a switch or a button on the relay package. What kind of GPS and nav radio do you have and is the system set up as an IFR system?
Northstar M3 GPS and King KNS 80 RNAV. It is set up for IFR operations. The switch no longer seems to be operating. Its currenly on NAV, and will not switch to the GPS. Its a pushbutton type switch, with the top half lighted when its on NAV, and the bottom half lighted on GPS.
Hello Scott: I doubt that the problem is the switch. You do have a remote relay which defaults to the NAV settings. Pushing the switch applies power to the relay which then goes to the GPS poles. I would check to see if you have dropped a power or ground lead some where.