Camera Trigger Relay

I’ve added a camera with a relay trigger to a hex which I’ve done many times before. While connected to the Cube via USB I am able to fire the camera via the digicam command. However, when I power the hex with it’s batteries I am not able to fire the camera in the same manner. As a sanity check, I flew a mission and was still unable to fire the camera. I’m assuming the basic settings must be right to be able to fire it from Mission Planner when connected via USB. I’m assuming that when fully powered something else gets assigned that is conflicting with Pin 55 (Aux6) but I can’t seem to see it. To verify I also did the same setup on Aux 5 with the same results. Any thoughts would be appreciated.

Check your relay wiring and make sure it is powered correctly (not from a servo ouput pin). And also check your ground wiring which has to be existing and common to the flight controller’s ground.

The relay is only connected to the signal and ground of Aux6. It fires when the Pixhawk is ONLY powered via USB and it is commanded from the UI. If I also power the Pixhawk from its battery then it does not fire. I have verified that the ground is correct.

I think that is the problem. How are your AUX ports powered ? What pixhawk board do you have ?