Can water short circuit a s9 plus or does the phone just need to dry.

Hi,

Here’s a description of the waterproof rating for the phone and what it means.

What you have to remember though is that is the condition that it left the factory in.

Its’ waterproof integrity after that depends a lot on how it was used (or abused) by the person who owned it. For example if it was regularly sat on (phone carried in back pocket of pants) or accidentally dropped once etc this could have slightly bent the frame or created a small crack which may have compromised its’ waterproof integrity.

You didn’t say how it got wet at the river, did it fall into the water? If it didn’t work after getting wet you would have to suspect that either the water caused the problem or if it did fall into the river, that the fall may have damaged something.

The only way to really know is to open it up and find out. Like most modern phones, the phone has liquid detection / liquid contact indicators inside the phone which will show when they have been in contact with water etc

Here are the ifixit Samsung Galaxy S9+ guides that may help with this.