Corrosion on the motherboard of my phone?

[AC Question]

My Galaxy S4 Mini SPH-L520 went through the wash. We put it in rice to let it dry out, and when we took it out the phone still seemed to be functioning normally except for the fact that the screen would not turn on. You can still unlock the phone and receive notifications, but the display remains black.
I took it apart and saw major corrosion and pitting on a metal plate on the motherboard. The number on the plate is the same as the model number on my phone. Is the corrosion on this plate affecting my phone's ability to work? If so, will I need to get a new motherboard in order to get it working properly? Thanks in advance for any helpful replies.

 

[B. Diddy]

Welcome to Android Central! Unfortunately, water damage can be unpredictable and widespread, so replacing one apparently corroded component doesn't mean there aren't also multiple other areas of damage. If you go down that road, you may end up spending more time and money than just replacing the phone.