Announcement

Collapse
No announcement yet.

A2159(820-01598) no image

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    A2159(820-01598) no image

    Macbook ProA2159 with board 820-01598 with black screen. was water damage. Measured lcd connector J8500 and find pin #1 (EDP_AUXCH_N) short to ground 2 ohm. Looks like it goes to U0500(CPU) directly . Is it anything to do? Starts fine and all, just no image
    Attached Files
    Last edited by liteott; 04-15-2021, 01:00 PM.

    #2
    Re: A2159(820-01598) no image

    Someone say that's CPU EDP partial Damaged. can it be fixed without replace the CPU(U0500)??? need solution please.

    Comment


      #3
      Re: A2159(820-01598) no image

      What’s it measure with display unplugged ?
      Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

      https://www.facebook.com/Telford-Tel...7894576335359/

      Comment


        #4
        Re: A2159(820-01598) no image

        Dead CPU. Backlight rail arced to eDP AUX line and killed it.
        OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

        Comment


          #5
          Re: A2159(820-01598) no image

          Diode mode 0.001 and 0.064v or 64mV on that pin#1. are there any way to rescue ? I am not able to replace the cpu or take it off to check if it is cpu dead or PCB board short.
          and is that "EDP_AUXCH_N" a power supply point or it's some data signal to activate the screen? can we use "EDP_AUXCH_P"--Pin #3(0.9V and 0.129 diode mode-- measured) to emulate it ?----sure need to cut cpu to pin #1 the trace first.
          for all your experts do you think to do this will damage more the cpu or screen I don't know how risky it will be at least use external monitor still can use this laptop and or the screen is not cheap.(if damaged)
          I am new for this hope got some advice thanks for all you guys.

          Comment


            #6
            Re: A2159(820-01598) no image

            Anyone have suggestions? thanks in advanced.

            Comment


              #7
              Re: A2159(820-01598) no image

              See post #4.

              Does this unit work with an external monitor? If possible, test with an external monitor. I know that we have done this with some external dongles to validate the position of the logic board.

              Also, we recently purchase a POST code reader for macbook and iMacs that apparently will confirm the boot cycle of the cpu. Bought from Asia but not yet used.

              That tool would help here. I think you stated earlier the logic board chimes? That is quite positive. Perhaps review your lvds connector and cable with all power off so no voltages cross onto other pins.

              Either way, you will need to know if your CPU is damaged beyond use or not.

              We are studying in how to replace large bga devices like such cpu but this will require a high quality bga rework station.

              Comment


                #8
                Re: A2159(820-01598) no image

                Everything will work except the internal display since the eDP output of the CPU is dead.
                OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

                Comment


                  #9
                  Re: A2159(820-01598) no image

                  For Mon2 yes it works on External Monitor.
                  Still I want to know if the "EDP_AUXCH_N" is power line or it's data signal line? can it be use "EDP_AUXCH_P" emulate add to eDP LCD? or it is feedback signal from LCD to CPU and let CPU know the LCD status then CPU will activated video functions or others etc...
                  Other thing I confirm the water damaged eDP LCD screen is good After cleaned LVDS EDP Display FPC Connector the connector was burned pin#43 and pin#1 became black color. and after cleaned I use A1706(820-00923-a) mainboard(that only working board I have) to test the eDP LCD with cleaned original flat flex video cable the video image came out perfectly.
                  Now How can I rescue this no inner video image mainboard.
                  Hope experts help me out thanks.
                  Attached Files

                  Comment


                    #10
                    Re: A2159(820-01598) no image

                    Hope you guys can help me: I bought same 820-01598 board from eBay (less than $200) try to replace that "eDP output of the CPU is dead" board but the board I bought had !"activation lock"! on it. my question is Can I just swap the SPI EEprom (U4770) to removal the "Activation lock"???
                    this board locked everything can not boot from external USB drive (secured not allowed) and tried to erase inner volume to reinstall and next boot up still there can not go in security manage utility to enable external drive boot.

                    thank you

                    Comment


                      #11
                      Re: A2159(820-01598) no image

                      I have a similar board in my hand. I also think the eDP of the CPU is partial dead.
                      Is there no chance to repair it without change the CPU?
                      Thank you!

                      Comment


                        #12
                        Re: A2159(820-01598) no image

                        The problem is: What about ME region after replace CPU. I was replaced CPU, board are start, but I can't open OS (ME corrupt, and just think what must to do to reset / replace the ME.) ? Just read 32mbit rom ic and have no found any signs of ME

                        Update: After replace cpu (with integrated pch) we must put Mac in dfu mode and restore the system. The ME is stored in flash memory or t2 ic. All data will be lost off course. In 15" and 16" there is no problem with ME after replace cpu.
                        Last edited by duchtesciowej; 01-04-2022, 09:36 AM. Reason: New knowledge

                        Comment

                        Working...
                        X