There are a couple of things that could likely be the problem, but first let’s check that the ST16 is generating the proper output signals before going into them.
Turn on the ST16 and once it finishes booting give the Volts icon a double tap. It will bring up a display that looks like this -
View attachment 24130
The tilt slider should change only CH7 from -100% (full up) to 100% (full down) +/-3.
The Pan Knob should change only CH8 from -100% (full right) to 100% (full left) +/-3.
The Tilt Mode switch is on CH9 and should read 10% (up & mid) and 100% (down)
The Pan Mode switch is on CH 10 and should read -100% (up), -40% (mid), and 100% (down).
Use the ‘back’ soft key to exit this display. Post your results.
The other issues range from a blown fuse in the aircraft to wiring problems from that point to the gimbal control board in the CGO3+. I’ll refer you to the CGO3+ section of the document in this thread
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