Seatalk Failure

[tholley55]

Hi, I'm looking for advice to troubleshoot a Seatalk network . The system is comprised of the Following : RL80C and RL70C Plotter/Radar MFD's, ST8002 Pilot, S3G computer, ST60+ wind, ST 80 Masterview, ST60 multiview. The system has worked well for the 7 years I've owed the boat, but recently it went into Seatalk Failure and nothing works. I get the message "no data" on the multi view and "Seatalk Failure" on the autopilot control head. I believe all the devices are in working order and suspect wiring. It's a model year 2000 Catalina 470 and I don't know where all the various junctions are located in the boat. My approach has been to bypass devices and wiring to hopefully get it to start up properly and then one by one bring on devices to see where the fault lies. However, even with taking everything offline (as far as I can tell), it still will not start without Seatalk Failure. My method (probably incorrect) has been to unplug the Seatalk wire at the Computer, which I assumed powered all the devices (except MFD's). I then plugged in a single known working device (wireless smart pilot) and restarted. However, it still fails. In view of this can you suggest diagnostic steps I should follow to find the problem ?

Tim Holley

Your advice would be greatly appreciated.

thank you,