THINKPAD L390 Not turning on after password remove

[RAR1991]

Hi, I've tried to unlock a ThinkPad L390 and used a patched file meant for another laptop but after putting back th e original dump the laptop refuses to power on. if there is anyone that has a solution I will be be very grateful.

[mon2]

Re: THINKPAD L390 Not turning on after password remove

Hi.

1) link a schematic or more details on the silk screen markings on the logic board.

2) Is the power adapter the typical barrel / coax round connector? Check the voltage to ground at the dcin connector. Check the same at every large coil. If you see a very low voltage then the power path has to be reviewed.

Which charger IC is on this logic board? This part should be near the 2 x DCin mosfets close to where the dcin connector is located. The charger IC is often the 'BQ' series from Texas Instruments.

Update: it is a usb c power delivery adapter. Check the voltage to ground on each grey coil to get started.

[RAR1991]

Re: THINKPAD L390 Not turning on after password remove

Thanks for the reply the Laptop is a ThinkPad L390_TYPE 20NU-S0Y400

MB Model : LKL-2 MB 18724-1M schematics attached. [MOD EDIT] Link to schematic - https://www.badcaps.net/forum/troubl...ga#post1562873

want just to precise that the laptop was working before the bios password remove attempt

[mon2]

Re: THINKPAD L390 Not turning on after password remove

Check the voltage to ground of each large grey coil. Any low or zero voltages ?

[RAR1991]

Re: THINKPAD L390 Not turning on after password remove

check the voltage to ground of each large grey coil. Any low or zero voltages ?

all voltages are present except for v core

[ktmmotocross]

Re: THINKPAD L390 Not turning on after password remove

for unlocking there is custom bios that can edit fw in T2 ic or other where is password stored. so u probably mess this fw.

[SMDFlea]

Re: THINKPAD L390 Not turning on after password remove

Hi, I've tried to unlock a ThinkPad L390 and used a patched file meant for another laptop but after putting back th e original dump the laptop refuses to power on. if there is anyone that has a solution I will be be very grateful.

Clean the ME firmware of the original bios backup,flash it back.Did you remove all batteries, is there a tamper switch on this model