Here is a list of components that can cause a Switch to not charge:
Battery
Charging Port
Charge Chip
-
Various other chips on the motherboard
+
Various other chips, diodes, resistors, capacitors, etc. on the motherboard
As Raffi said, you would need a multimeter to check to see if these were bad. You would also need a hot air station, flux, solder, and a soldering iron to fo these other motherboard-level repairs.
Another thing you could do is to replace the motherboard. However, a new motherboard will cost about $180.
Here is a list of components that can cause a Switch to not charge:
Battery
Charging Port
Charge Chip
Various other chips on the motherboard
As Raffi said, you would need a multimeter to check to see if these were bad. You would also need a hot air station, flux, solder, and a soldering iron to fo these other motherboard-level repairs.
Another thing you could do is to replace the motherboard. However, a new motherboard will cost about $180.