We are currently about 500 nm west of San Diego en route to the Marquesas. My Raymarine ST6002 SmartPilot was working when I went into a Marina in San Francisco but when we came out the control display is reading "Seatalk failure" and the unit doesn't work. My manual says to check connections. I've checked the Seatalk connection in the back of the instrument pod and also the connections going into the computer. There is also a 2 amp fuse on the board next to the Seatalk connection. There is still continuity on this fuse. Nothing I've tried changes the error message. Any ideas on things to try bearing in mind how far offshore I am? I was wondering if our recently installed NMEA connections or else the proximity to the now actively used Icom AT 140 antenna tuner for my Ham radio may have caused a problem or caused RF interference. Just a thought. Anyway if you have any ideas on things I could try it would be much appreciated.
Confirm the wire continuity on the following: