My phone drop in water

@kennn

The first step is to not try to restart/sync the phone. This may further damage your phone. Remove your battery asap The next thing to do is to clean it. Disassemble your phone using this guide Xiaomi Redmi Note 4X LCD Screen Replacement . You must remove all the EMI shields of the logic board. If you do not remove those you are not cleaning your board properly. Clean everything with +90% (no less than 90%) isopropyl alcohol. Follow this guide, and even so it was written for an Apple iPhone, all the points are still pertinent to your phone. Pay particular attention to the SMD components, check for charred, missing or broken components. You can then dry the board in an oven or equivalent at 220deg F (not higher;-) for a few hours. Best way to clean it would of course be through an ultrasonic cleaner. Consider professional help with that When it is properly cleaned, replace the battery. Replacing the battery is a must since any immersed battery will eventually fail (sooner than later). Only after all this can you diagnose what is really going on with your phone. You cannot properly diagnose your phone until you got that issue resolved.