Controller won't link the the Phantom4

[Mooneypilot]

I am on the latest iOS and have updated the firmware on the phantom. Now the controller will not link with the drone. I am getting a red light. I have tried multiple iOS devices as well as numerous cables. Still will not connect. I have another Phantom4 I bought to protect myself since I have a job on Tuesday. That unit links fine, but I have not updated the firmware. I wonder if that's the problem? Any ideas?

 

[Prairie Pyro]

You have not stated anything of updating the RC. Latest updates now require both the AC and RC to be done.

 

[hotelzululima]

update the P4 drone with the long USB cable and the latest DJI assistant app downloaded from www.dji.com

hzl
ps this **** ruined a shoot out in the boonies with no internet available to update from..