gps connection fuel management

[<tipster>]

Can anyone supply the wiring directions for connecting the FMS to a raytheon R620+ with a R120 gps antenna ?

[<boats.net>]

I don't have Raytheon wiring diagram but there is a number in the operation manual you can call Raytheon to help with GPS connection. You want to connect the White wire from fuel management gauge to the NMEA 0183 output lead of GPS do not use Red and Black FMS wires and set switch in back of FMS to GPS.

[<texduck88>]

I have interfaced the NMEA 0183 output to the input of the Fuel Management System (FMS) using the whit wire from the FMS to the positive (+) 0183 signal. The FMS does not seem to recognize the 0183 input as fuel economy in units of miles per gallon is blank. I think that I need to change a switch on the FMS but my owner's manual doesan;t say how, where, etc? Can anyone help with the switch?

Thanks,
Mark