The solution to the problem that the light does not come on after the PS4 controller is flooded with water is:
1. Unplug the PS4 controller and disassemble it.
2. The hair dryer turns on cold air, not hot air.
3. Put a few paper towels that are absorbent and will not break. Put the dry powder packet that comes in the hard drive package in the box on top of the paper towels. Leave it uncovered in a cool place. 2 days.
4. Take out the paper towel and dry powder bag, and install the handle.