Multiple shorted caps

I bought a broken Switch for 20€ and thought I could try repairing it. So I just started poking around with my multimeter and found out that some ICs has shorted caps. Here’s the list:

  • MAX77621AEWI+T
  • MAX77620AEWJ+T
  • SoC

Other things I figured out where that it draws 0A, the fuse is good, the battery charger receives 0,1V and that the previous owner tried to reflow the SoC so this might be beyond saveble. So all Im asking is if this is repairable, is it worth repairing or do I keep it for parts.

What’s the resistance?

Most likely a short on your SYS rail caused by BQ IC fault or because of a failure of M92 IC, I would also verify that no USB pins are bent inside and that the USB has had no prior rework to rule out a bad install

Given the previous owner attempted an SoC reflow then the chances are slimmer, if the resin round the die is still a greyish/blueish colour there’s a chance, if it’s brown I’d use this board as a donor

https:// imgur. com/nFZpX2K

MAX77620AEWJ+T on all shorted caps it shows 60
MAX77620AEWJ+T and SoC show 76

Doesn’t look too bad, though bit hard to tell from a photo, your better off comparing it to another board if you have one

Theyr’e not shorted if that’s ohms

Can you check resistance to ground on your SYS rail, this can be found at the 2R2 coil near BQ IC, one probe on ground and the other on any side of that coil. also check the caps around M92 and see if any are short

I notice from your picture that the EMMC module is not present, can you confirm if you have this and it’s just disconnected?


The upper part by the SoC was covered with flux so I disconnected everything to clean it.

None of them have shorts

That’s fine

I see


I’d give the board a really good scrub and remove all the nasty flux residue on the board, after I’d verify USB has continuity to all relevant destinations with a USBC breakout board, if all is well on that front I’d replace M92 IC, if no change I’d replace BQ IC

After cleaning it and fully drying I plugged into power again it now draws 0.16A and there’s a high pitch sound coming from somewhere around the SoC