Announcement

Collapse
No announcement yet.

macbook A1932 820-01521-A

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

    macbook A1932 820-01521-A

    Hi all ! I really need help with my motherboard! consumption 20V / 0.060-0.280 A is unstable! not detected in DFU! There is no picture on either the external or internal monitor!
    PPBUS_G3H=12,61v
    PPBUS_HS_CPU=12.61v
    PPDCIN_G3H=19.94v
    PP5V_G3S=5.12v
    PP5V_S5_LDO=5.12v
    PP3V3_G3H_RTC=3.3v
    PP3V3_G3H=3.3v
    PP3V3_G3SSW_SNS=2.3-2.6v is unstable!
    PP3V3_G3S=3.3v
    PP3V3_TBT_X_S0=0v
    PP2V7_NAND=2.513v
    PP1V8_G3S=1.8v
    PPVCC_S0_CPU=0v

    #2
    PP3V3_G3SSW_SNS=2.3-2.6v is unstable!
    Remove all power -> meter in resistance mode -> measure the resistance to ground. Someone on this 'sensor' dedicated power rail is consuming too much current and causin this voltage fluctuations.

    Also review / reflow the load switch @ U8225. It is this load switch that passes the PP3V3_G3H to power these sensors. Be sure that PP3V3_G3H is stable @ U8225.

    Click image for larger version

Name:	sensor_load_switch.png
Views:	167
Size:	264.1 KB
ID:	3267956

    Comment


      #3
      PP1V8_SLPS2R 1.8v but 0.003 diod mode

      U8225
      1=3.3V stable(6.7kohm)
      2=0v (3.89 mohm)
      3-4=3.3V stable(6.7kohm)
      5-6=2 .3-2,6v unstable(0.436mhom)
      7=2 .3-2,6v unstable(5mhom)

      Comment


        #4

        Comment


          #5
          Not sure what is going on here since there is no short on the consumer side of this load switch.

          If you wish to experiment, swap this Silego part used here with another from a donor board or even from U8210 or U8220. The same component is present at these locations. Being a 4A rated load switch, it should be able to handle ample current but it is possible the part is defective.

          If the next part behaves the same then there is some other fault.

          Comment


            #6
            PP1V8_SLPS2R 1.8v but 0.003 diod mode

            Comment


              #7
              Cannot be both. With no power and meter now in resistance mode, measure the resistance to ground of this power rail. Post the measurement.

              Comment


                #8
                the problem was in the CD 3215, after replacing the poppy came back to life but did not undergo activation

                Comment


                  #9
                  Has anyone encountered this and how to solve the problem?

                  Comment


                    #10
                    How to Fix "The Recovery Server Could Not Be Contacted" Mac Error (howtogeek.com)

                    Comment


                      #11
                      HI.the problem is that there is no terminal and utility section

                      Comment


                        #12
                        Can you attempt to install the MacOS over USB media?

                        Comment


                          #13
                          Originally posted by mon2 View Post
                          Can you attempt to install the MacOS over USB media?
                          I have the same problem with USB, it asks me to activate my MacBook.

                          Comment

                          Working...