a dog chewed this customer’s USBC charging cable and bricked their lenovo yoga laptop! also a convoluted repair! let’s take a closer look at this mid 2018 lenovo yoga 920-13IKB ideapad.

this laptop would not fire up. you can see in the middle of the following short vid that the keyboard backlight was pulsing off and on, and you could also faintly hear it. i pulled the motherboard and found a hotspot using some IPA on area PU11. this chip was hot! so weird to see the heartbeat of the current visible in the liquid as it pulsed.

this chip was listed on the schematic as OZ7502_CSP8 and as a bga8 – a BGA chip with 8 pins.

i pulled the chip to see what kind of damage may be underneath and to see if the short would be relieved. once pulled, the pulsing stopped, but the rest of the board got extremely hot. i ended up reballing this chip and reinstalled it later one. i took a cool closeup of it and posted it to my instagram page here.

so felt around on the board, and the hottest seemed to be by the audio jack/fan. this time, i pulled out my freeze spray and took a video. i like to video so that i can see what heats up first and to play it back slowly.

if you look closely, the diode D6 evaporated first, then U37. D6 is listed on the schematic as (BAS521_SOD523) and U37 is (AP2204K-3.3TRG1) voltage regulator.

so i removed both of those. still a short to ground. the hot spot had moved. applied the freeze spray again. it was now on U36. this chip is listed as CYPD4226-40LQXIT and is a dual USB Type-C port controller. this is all starting to make sense. it’s like i’m working my way back to the charging port which is where all the trouble seemed to begin with the charging cable chewed by the dog.

i removed U36 and my short was gone! i didn’t have this chip in stock, but digikey did and i placed an order.

on a side note, the drive used in the machine is an PCIe x4 M.2 SSD – NVMe M key. to read the drive, i would need an adapter. the adapter i would be looking for would be an NVMe m.2 to SATA adapter. BUT!! apparently NVMe can’t communicate with the SATA bus. it requires a direct connection to PCI-E. if you can shed some additional light on this area, please leave a comment below. it may help us all in the future with data recovery, should we not be able to fix the motherboard. is the only simple option available is to find another motherboard to recover the data? leave a comment if you have some insight. i had moved on at this point, as the repair was successful and didn’t have to worry with the data. i had bought what i thought was an adapter years ago, but when it arrived, i found i would not be able to use it. i should have looked closer at what i was ordering before i ordered it. check out this thing…

thanks for looking over my shoulder. can i help you with anything? if so, contact me here.