Bios unlock for DELL LATITUDE 7420

[nafienew]

Hello, I have this Latitude 7420 laptop with bios password,
please removed.

Latitude 7420
ST: 6VD64M3

[peste]

Hello, I have this Latitude 7420 laptop with bios password,
please removed.

Latitude 7420
ST: 6VD64M3

try..

[nafienew]

try..

It works thank you

[trunguntilyou]

Latitude 7420

Service Tag: 9TPC7M3
,, pls help me! tpm is not detected

[lapfix]

Latitude 7420

Service Tag: 9TPC7M3
,, pls help me! tpm is not detected

Bios Version : 1.42.0
Me Version : 15.0.50.2633

[trunguntilyou]

Bios Version : 1.42.0
Me Version : 15.0.50.2633

Thanks !! works perfectly

[tony_v]

i see at the picture that UC2 is desoldered , and this one must be 32 mega : W25R256JVEIN...
that's our chip with a bios pwd....the one you post it at post #426 is 16 mega

Hi, I have the motherboard with the exact same model: GDC31 LA-K371P, rev. 3.0. ( A02), but the UC2 chip is different from what you mentioned, it's GigaDevice 25R256DYIG, is it correct?
I will desolder and read it, I assume it's just another manufacturer, but the same chip and the password is there.

[lapfix]

Hi, I have the motherboard with the exact same model: GDC31 LA-K371P, rev. 3.0. ( A02), but the UC2 chip is different from what you mentioned, it's GigaDevice 25R256DYIG, is it correct?
I will desolder and read it, I assume it's just another manufacturer, but the same chip and the password is there.

Yes it's correct , just another manufecturer...so desoldered it , read it and post it here

[tony_v]

Attached is the file, can you please check it?
Latitude 7420
Service tag HF8DGK3
Bios chip: GigaDevice 25R256DYIG

One more question - I read the chip using CH341 programmer and it works as usual, I can erase it ok, but when I start flashing it with an original bios, the process hangs the programmer (tried AsProgrammer and NeoProgrammer both programs just hang and stop responding). If i stop the process and read the chip again, I see that only some blocks of the firmware are written correctly and then all the subsequent memory is empty. Did you ever meet such an issue? I think it might fail writing the modified firmware as well.

Could it maybe be connected with a strange behavior of chip write protection: I can't fully remove write protection bits for some reason. Some flags just return back even after I remove them. See the screen attached.

[tony_v]

Not sure why, I don't see zip archive with the bios attached to my previous message while I am not logged in. Uploading the dump in rar format once again just in case.

[tony_v]

Anyone knows what are the correct settings for the status registers here for GigaDevice 25R256DYIG on Latitude 7420?
Looks like I've tested everything else but these bad boys. And I unfortunately didn't save their initial configuration settings before resetting them (

[GlobalSerwis]

Please help me remove BIOS password.
Dell Latitude 7420
LA-K371P Rev 3.0 (A02)
ST : GXMGMN3

[lapfix]

Please help me remove BIOS password.
Dell Latitude 7420
LA-K371P Rev 3.0 (A02)
ST : GXMGMN3

1st boot, press F2, write service tag, disable Absolute, save, restart.
2nd boot press Alt+F to exit manufacturing mode.
Good luck.

[GlobalSerwis]

1st boot, press F2, write service tag, disable Absolute, save, restart.
2nd boot press Alt+F to exit manufacturing mode.
Good luck.

Thank you very much, the bios works perfectly. 🙂