Just got my Phantom 4 pro plus a couple of weeks ago. everything worked great out of the box. Last nighjt did a firmware update and now my camera doesnt work?  Screen is compleatly grey.

Did you update your controller firmware also, or just the craft? It depends on what was on the craft originally, of course, as it may not be required.

Regardless, it sounds link your controller and craft haven't linked. Are the LEDs on the controller and craft green or red? If red, try resetting the controller and linking manually.

Resetting the controller:

* Have the controller off and press down C1 + C2 + red record button (top left) + ISO Dial (top right wheel).
* While still holding down, turn the controller on and keep holding for about 5 seconds.
* Release.

Bam! The controller is reset. You may then need to re-link the controller and craft manually:

* Turn on both the aircraft and the controller.
* Press C1 + C2 + record button on the controller, then the controller will beep like D-DD.
* Let go all fingers, press the wheel on the right side of the controller and then the first LED on the controller will become blue and it will constantly beep DDDD.
* Use a paperclip or toothpick to push in the linking button on the craft (near the SD slot) and hold for 3-5 seconds, remove and wait. It should link after a few seconds.