I'm fairly sure most P4 users have resolved the Red / Green flashing LED and no video image feed problems some of us had during November and December 2017.  If not, then I have up loaded a YouTube video to help people follow the process that I had written about on a couple of threads.  There is new DJI GO 4 which might have solved this problem by now also.

Anyway hope it helps !

      

"There is new DJI GO 4 which might have solved this problem by now also."

Correct, in fact two releases now since DJI Go 4 V4.1.18 bug stopped the RC updating. So RC should update using DJI Go 4 latest version via the Aircraft Status menu.

Edit:- And of course it was only the iOS version of V4.1.18 that was affected. So another resolution would have been to use an Android device to update RC.

Thanks for sharing with us. The new version has been released and fixed the issue in IOS V4.1.18. If you encounter the similar issue, feel free to contact us.