Fellow Sea friends,

I'm unable to connect a Garmin GNX20 marine instrument to Nexus NX2 server.

GNX20 has 2 ports, one for NMEA2000(normal 5 pin) another NMEA0183 with 7 pin. As instructed by the brand got power to the device using the NMEA2000 port 5 pin, cable spliced, using red and black wire to give the 12v to the GNX20. Since the NX2 network is NMEA0183, Bought from garmin the 7 pin cable and connected it to the NMEA0183 port of the instument, using only 2 wires, Brown: Rx/A (In+) connected to the NMEA Output (+) of the server and Green: Rx/B (In-) to the NMEA Output (-) of the server.  

GNX20 instrument powers up but no data values are interpreted. With the multimeter I detect that random low current typical of NMEA0183 data. Connected laptop with opencpn to the server and NMEA sentences are running (although they have the "II" on the beggining, dont think that the problem), other repeaters all from nexus are working fine...Tried to connect the black wire from the 7 PIN cable to common ground as some manuals suggest but nothing.

What am I doing wrong?

Thank you all and Bons ventos