Lenovo thinkpad E590 - NM - B911 board - Not turning on USB C damage

[worldofskin]

Hi guys hope you are having a great day, this Lenovo came to the shop with a demolished usb c connector becouse the laptop has fallen on ground. Especially on the usb c connector. after replacing it i measured a 5ohm or lower resistance to ground on some pins around usb C connector on the ESD protecting diodes. On the RTS5455 pin 18 that is TYPEC_RXP2 had 5ohms to ground. After taking the ic off all the shorts were gone other than USB20_P2_CON and USB20_N2_CON with 3ohms. Those lines go to the PCH = CPU if i am not mistaken. i tried to measure other usb 2 lines and they are in the 3ohm realm.
Resistance to ground on power rails

+1.05VALWP rail : 1 Ohm
+VCC_CORE 4 Ohms

When i try to power on the laptom with battery. ALWP rails are on 5v, 3,3v, 1,05v. S3 rails are off. The PCH side of cpu gets pretty toasty but not too much.

I think after the USB C damage cpu got a hit through the usb2 lines.

Thanks in advance )

[reformatt]

Re: Lenovo thinkpad E590 - NM - B911 board - Not turning on USB C damage

+1.05VALWP rail : 1 Ohm

Usually a reading that low, it's a fried PCH. Your USB readings indicate the same. You could inject 1V into this rail and inspect with a thermal camera. Usually the PCH lights up, confirming the diagnosis.