Bios unlock for DELL LATITUDE 7420

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  • LBTT1121
    Badcaps Veteran
    • Nov 2024
    • 864
    • Viแป‡t Nam

    #501
    Originally posted by srsyed1

    Original and patched both file attached
    model dell 7420
    board number LA-k371P
    load bios on original IC

    Comment

    • srsyed1
      Member
      • Mar 2024
      • 29
      • United kingdom

      #502
      I did load on original ic its still same . Is it ic problem?

      Comment

      • Markus1741
        Badcaps Veteran
        • Sep 2020
        • 942
        • N/A

        #503
        Originally posted by srsyed1
        I did load on original ic its still same . Is it ic problem?
        Hello try this new build file from your orig bios file ....
        Attached Files

        Comment

        • srsyed1
          Member
          • Mar 2024
          • 29
          • United kingdom

          #504
          Originally posted by Markus1741

          Hello try this new build file from your orig bios file ....
          Now just fan spin keyboard light and after 30-40 sec reboot .

          Comment

          • Markus1741
            Badcaps Veteran
            • Sep 2020
            • 942
            • N/A

            #505
            Originally posted by srsyed1

            Now just fan spin keyboard light and after 30-40 sec reboot .

            Yes, then everything is fine. That's the unlocking process. You'll have to be more patient. The Dell laptop can restart up to four times, and you'll then have to re-enter your service tag.




            Comment

            • srsyed1
              Member
              • Mar 2024
              • 29
              • United kingdom

              #506
              Originally posted by Markus1741


              Yes, then everything is fine. That's the unlocking process. You'll have to be more patient. The Dell laptop can restart up to four times, and you'll then have to re-enter your service tag.



              Hi thanks but its keep doing rebooting almost 30 times now. Still same no display and after keyboard light 30-40 sec just rebooting.

              Comment

              • LBTT1121
                Badcaps Veteran
                • Nov 2024
                • 864
                • Viแป‡t Nam

                #507
                Originally posted by srsyed1

                Hi thanks but its keep doing rebooting almost 30 times now. Still same no display and after keyboard light 30-40 sec just rebooting.
                bios ok , replate IC bios

                Comment

                • srsyed1
                  Member
                  • Mar 2024
                  • 29
                  • United kingdom

                  #508
                  Originally posted by LBTT1121

                  bios ok , replate IC bios
                  Changed bios chip and flash provide file still same.and with provided file i can see backlight on display but no logo nothing . With 3 red 5 white flashing light .And after flash with original again same . ๐Ÿ˜”

                  Comment

                  • srsyed1
                    Member
                    • Mar 2024
                    • 29
                    • United kingdom

                    #509


                    I replaced the BIOS chip and flashed it with the file you provided. The laptop powers on and I can see the display backlight, but thereโ€™s no logo or image. The indicator lights flash 3 red and 5 white repeatedly.




                    When I reflash the original BIOS file, the screen only shows a whiteโ€“blueโ€“redโ€“green color pattern.
                    i think my original file got corrupted .can you please help me on this. As i changed 4 new chip all same

                    Comment

                    • bretta
                      New Member
                      • Jun 2025
                      • 4
                      • Pk

                      #510
                      help needed to unlock bios pwd

                      dell latitude 7440
                      bios 1.21.2
                      memory 32 gb
                      service tag 1z1zdy3
                      express service code 4296429147


                      thankyou.

                      Comment

                      • LBTT1121
                        Badcaps Veteran
                        • Nov 2024
                        • 864
                        • Viแป‡t Nam

                        #511
                        Originally posted by bretta
                        help needed to unlock bios pwd

                        dell latitude 7440
                        bios 1.21.2
                        memory 32 gb
                        service tag 1z1zdy3
                        express service code 4296429147


                        thankyou.
                        attach bios

                        Comment

                        • bretta
                          New Member
                          • Jun 2025
                          • 4
                          • Pk

                          #512
                          i cannot retrieve bios. it is locked,
                          it is available as current or latest exe file on dell webite.

                          Comment

                          • bretta
                            New Member
                            • Jun 2025
                            • 4
                            • Pk

                            #513
                            Originally posted by LBTT1121

                            attach bios
                            i cannot retrieve bios. it is locked,
                            it is available as current or latest exe file on dell webite.

                            Comment

                            • bretta
                              New Member
                              • Jun 2025
                              • 4
                              • Pk

                              #514
                              Originally posted by LBTT1121

                              attach bios
                              https://www.dell.com/support/home/en...driverid=2v9mf
                              search tag, 1z1zdy3-8fc8

                              latest ver is available here,

                              Comment

                              • LBTT1121
                                Badcaps Veteran
                                • Nov 2024
                                • 864
                                • Viแป‡t Nam

                                #515
                                Originally posted by bretta

                                https://www.dell.com/support/home/en...driverid=2v9mf
                                search tag, 1z1zdy3-8fc8

                                latest ver is available here,
                                post the original contents of the bios chip..not the update on the website..
                                The bios chip must be unsoldered from the board before writing or reading..
                                do not use the clip, you may have errors..if you do not have anything to unsolder it with,
                                solder wires between the programmer and the bios chip..

                                you need an SPI programmer

                                Comment

                                • Murtaza527
                                  Badcaps Veteran
                                  • May 2018
                                  • 259
                                  • Malaysia

                                  #516
                                  Hi everyone please remove the lock from this bios its Dell 7420 model service tag # F88Y7D3 express : 33150497223
                                  Attached Files

                                  Comment

                                • LBTT1121
                                  Badcaps Veteran
                                  • Nov 2024
                                  • 864
                                  • Viแป‡t Nam

                                  #517
                                  Originally posted by Murtaza527
                                  Hi everyone please remove the lock from this bios its Dell 7420 model service tag # F88Y7D3 express : 33150497223
                                  try and feedback
                                  Attached Files

                                  Comment

                                  • Murtaza527
                                    Badcaps Veteran
                                    • May 2018
                                    • 259
                                    • Malaysia

                                    #518
                                    thank you very much and that link is very useful for next i will try it myself

                                    Comment

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