820-00923 - no power

Alan.L

Member
the laptop was liquid damaged but I can't find any liquid on the board. The board was still working then customer changed the screen because liquid got into the screen then a few days later the touch bar has stopped working then the customer reboot the laptop and has stopped powering on.

fan spin, no light on USB mouse and the cpu is little warm.


PP20v -19.9v
ppbus_g3h - 13v
CPUVR_PGOOD - 3.3v
ALL_SYS_PWRGD - 3.2v

PP3V3_G3H - 3.3v
PP3V0_G3H - 3.0v
PPVCCPRIMCORE_SUS_PCH - 1v
PP1V2_S3 - 1.2v
PP1V2_S0SW - 1,2v
PP1V8_SUS - 1.8v
PP1V8_S0 - 1.8v
PP3V0_G3H - 3v
PP5V_S5 - 5.1v
PP5V_S0 - 5.1v
PP3V3_S5 - 3.3v



PPVCC_S0_CPU 0v
PPVCCGT_S0_CPU 0v

Resistance to ground on PPVCC_S0_CPU = 7 ohms


RIP CPU?
 
Last edited:

Alan.L

Member
Check resistance between PPBUS and PPVCC_S0_CPU. Is the CPU getting warm at all?

yes cpu getting little warm.



you reckon U7210 has killed the CPU?

the resistance between PPBUS and PPVCC_S0_CPU: 1.0 M ohms
 
Last edited:

JohnB8812

New member
It is definitely possible it died. PPBUS not being shorted to VCore is a good sign tho. If you plug in a USB mouse through an OEM USBC-USBA dongle, does it light up?
 
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