I purchased a Nintendo Switch with a joycon pairing issue (won’t register joycons).
Initially when I opened the Switch, some ribbon cables were disconnected which I found strange. After reconnecting the ribbon cables, the left joycon rail started to smoke. It burnt out the chip on the rail itself.
Fast forward a few weeks, new joycon rails arrive.
Now the right joycon is detected, but the left joycon is not (battery side).
The controller does not appear to be charging, tried a known-good controller and still no-go.
Pulled the board out, no signs of corrosion, checked caps on the left rail circuit, but no evidence of anything shorting. I’m kind of at a loss here.
Because there’s no schematic it’s difficult to track where the left joycon rail is going (circuit wise).
I have attached a photo of the board, front & rear.
Any further assistance or insight would be greatly appreciated.