Seatalk converter ST60+not on ng backbone

[Alvin]

Thanks Chuck,
Devices and connectios:
Autopilot Actuator: T piece with spur to Actuator, Terminator, Seatalk ng backbone to >
Seatalk-Seatalk ng Converter: Spur cable to P70 Autopilot controller, Spur cable to EV200 Evolution, Seatalk adapter cable to ST 60+ Depth meter, Seatalk ng backbone cable to>
5 way connector: Seatalk spur to MFD a78 power, Seatalk ng spur to MFD a78 network, unused spur connector (no blanking plug), Seatalk ng backbone to>
T connector: Spur to i60+ wind instrument, Terminator
Only power connection to backbone is from MFD a78. The depth instrument ST 60+ has power and a red line in the spur adapter cable to the converter. This is the only Seatalk device connected to the converter.
MFD, Wind, autopilot all connected working normally. Depth not displayed and MFD find device, not found. Blank display for depth.
Simple test for depth on backbone? Thanks, Alvin