Chosen Solution
820-3115 - B. Green light on charger but won’t power on, no fan. When I first plugged it in I noticed smoke coming form under the heatsink so I took it off and started inspecting, which didn’t take long because I found some exposed copper staring me in the face. I found a board view and schematic and believe this to be R5410. Any advise on how to proceed would be greatly appreciated.
Very common issue in this area, have 3-5 3115’s with exactly the same issue. A lot of the time, there is a short to ground inside the board, but sometimes PPBUS_G3H gets shorted to R5347 (low resistance to ground), which pulls PPBUS to ground. In your case, it looks to be the latter, but measure for a short to make sure. The 4 vias the left of R5410 should not be attached to the area to the left of the resistor (spotty area) or the resistor itself. You may be able to separate these areas by digging slightly, mainly around the bottom via since it is likely joining to this area under where it is burnt (which would have merged the board slightly). If you need to dig more than 2mm, I would advise against repairing it, it can be a potential fire hazard and you can usually see the board spark where the voltage is too close to ground. If you can cut the trace to separate it enough however, definitely worth repairing.
