Ground short on M92 pad without M92 on

Nintendo Questions Nintendo Switch
1

Hi all! I have a Switch HAD-CPU-01 motherboard that has a short to ground on one of the M92 caps, with the M92 off the board. The short is there with the cap off too. Looking at the schematics, this pad connects to the Mp92 pin 16 (a GPIO pin) and pretty much any other components - so, I suspect this to be a voltage rail, and I suspect that this is likely to be a bad CPU or memory chip.

But I was wondering, is there a fixable culprit that is usually associated with a short there?

I don’t seem to be able to include images or links in my posts, but it’s the large cap at the bottom-right side of the M92.

Thank you!

2

That sounds more like pin18 on VDDIO not pin16, which means you have short on 1.8v power line generated by MAX77620H on the back. From my notes, 1.8v line should have around 1.6K~1.7K ohm to ground

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3

Thank you jkyoho, you are right, it’s pin 18, VDDIO! I’ll have a look at the MAX on the back now.

4

Unfortunately the short is still there with the MAX out :frowning:. I don’t think I’ll be able to bring this one to life

5

if you have bench supply and thermal camera, voltage injection may give you a hint on what exactly caused this power rail short. Unfortunately 1.8v rail short in general leads to a cpu short