Not power on and not RCM but low resistance in D- usb test_pad

Greetings everyone,

I hope you’re all doing well.

I’m currently facing an issue with a Switch V2 CPU (HAC-CPU-20) that refuses to power on, despite normal charging (the battery registers 4.18v). When pressing the power button, the current drain is holded in 0.34A, but there’s no display signal, leading me to suspect it might be stuck in RCM mode.

I’ve meticulously checked the entire board for shorts, but none were found. The only exception is the D- test pad indicated in the image:


The reading for point 3 on D- is 0.020 in diode scale!

I’ve scrutinized the area around pi3usb in diode scale, and everything appears to be in order. I’m curious about the IC response for D- and what further tests I should conduct.

Your insights and suggestions would be greatly appreciated.

Thank you! sorry my english is not mother language

I forgot! The USB is not recognized.

REMOVE this ic if you have one on your board and see if d- diode reading back to normal

Now that I realized that this IC (integrated circuit) was removed because it’s not on the board!
This board came from another repair service!
So yes, the cost remains the same!

Then it would either the port or CPU having short.

the line is directly to CPU ?

Yes, nothing else control d+ or d-, CPU direct