[duffer1960]

I have an autohelm ST4000 with an older version wind speed and direction display, and speed log/depth display. The log/depth display works correctly, but the wind speed/direction does not. It will display apparrent wind speed (= hull speed) but not direction. All of the connections at the mast are good. How can I troubleshoot the instruments without going up the mast? Should I be able to measure a voltage or resistance on the wires running to the masthead relative to the wind speed and direction? If so, what should I see on what wires? This would tell me that those are working, and the problem is from there back. Vice-versa, is there it possible to connect a voltage or resistance across some input pins to the ST4000 and induce a reading that way?

Any information will help.

Thanks.