How to change, update, reflash firmware in DJI PHANTOM 4?
Necessary Tools and Drivers
- Internet access.
- USB-C cable.
- DJI Assistant 2 For Mavic software.
- Computer with Windows 7/8/10 onboard.
WARNING!
Firmware reflashes on the drone will erase all of your data.
All described operations you are doing at your own risk.
If want saves your data do a backup before start.
The battery should be at least 50% charged before the start.
Hard Reset, Firmware update / reflash / downgrade manual for DJI PHANTOM 4
When you're ready you can follow this simple manual.
- Download and install DJI Assistant on computer.









- Turn on the DJI Assistant on computer.

- Connect DJI drone to USB-C cable and to computer.
- Next press the power button on DJI drone, then again press and hold the power button until see that DJI drone will turn on and warm up.
- Then on DJI Assistant show DJI drone icon.

- Tap on it, then tap on firmware update box.


- Use the reflash button to change firmware in DJI drone or factory reset it.

- Next, wait until all process ends with success with communicating in DJI Assistance software.




Excellent job, factory reset, firmware update, firmware reflash is finished.
https://www.hardreset.info/