Diagnosis For Loss of Power Input on A1370

Salutations fellow fixers,

I am new to the repair game, but confident in my technique and ability, but weak in experience.

I am repairing a friend's 11" 2010 C2Duo MacBook Air.

This machine used to power on all the time, and the battery is fine; it was at 380 full cycles and worked perfectly.

It has been subject to water damage in the past, but appears to have a functioning logic board.

From the time he showed it to me until now, the charging was spotty and the MagSafe connector had to be unplugged and replugged several times before the light came on and the battery charged. The MagSafe brick works well on another machine.

Recently, the machine has completely stopped charging, as well as turning on.

My questions to the professionals are:

-Where/how is the MagSafe port connected to the rest of the machine?

-Does power move from the port to through the logic board and to the battery?

-If so, which connection is likely broken, the port to board, or battery to board?