Macbook Pro A1989 - 820-00850 A no boot

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  • obelix24
    Badcaps Veteran
    • Jun 2023
    • 291
    • Slovakia

    #21
    no i haven't

    Comment

    • hopkok
      Senior Member
      • Oct 2014
      • 178
      • Slovakia

      #22
      Hi masters, I have this machine on bench, came with not working keyboard and trackpad. I found shorted can on trackpad power line. So I solved it, keyboard and trackpad start working, but now FANs run at full speed and MAC is very very slow, cant reinstall iOS either...

      Do you have any sugestion what can be the culprit? I tried new trackpad, but the same issue.
      I double checket battery data line cable and there is good continuity too.

      Many thanks for any tips.

      Comment

      • mon2
        Badcaps Legend
        • Dec 2019
        • 14147
        • Canada

        #23
        Carefully - Measure the voltage to ground of each pin on the battery connector. Post each measurement.

        Comment

        • hopkok
          Senior Member
          • Oct 2014
          • 178
          • Slovakia

          #24
          Will back to work tomorrow or Monday, today had to leave. Need to assembled it. Will post measurement. Thanks

          Comment

          • hopkok
            Senior Member
            • Oct 2014
            • 178
            • Slovakia

            #25
            Originally posted by mon2
            Carefully - Measure the voltage to ground of each pin on the battery connector. Post each measurement.
            1-0V SYS DETECT L
            2-3,3V BAT SCL
            3-3,3V BATT SDA
            4-0V BMON IOUT
            5-0V GND
            6-0V not connected

            Comment

            • mon2
              Badcaps Legend
              • Dec 2019
              • 14147
              • Canada

              #26
              SMBUS lines are not shorted.

              what is the voltage to ground of ppbus_g3h ?

              Comment

              • hopkok
                Senior Member
                • Oct 2014
                • 178
                • Slovakia

                #27
                ppbus_g3h 12,6V

                Comment

                • mon2
                  Badcaps Legend
                  • Dec 2019
                  • 14147
                  • Canada

                  #28
                  Review & post the voltage to ground measurements for:

                  I2C_SNS1_S0_SCL
                  I2C_SNS1_S0_SDA

                  I2C_SNS_G3S_SCL
                  I2C_SNS_G3S_SDA
                  Last edited by mon2; 01-29-2024, 08:09 AM.

                  Comment

                  • hopkok
                    Senior Member
                    • Oct 2014
                    • 178
                    • Slovakia

                    #29
                    Hi,

                    I2C_SNS1_S0_SCL - 1,6V
                    I2C_SNS1_S0_SDA - 1,6V

                    I2C_SNS_G3S_SCL - 1,8V
                    I2C_SNS_G3S_SDA - 1,8V

                    Comment

                    • mon2
                      Badcaps Legend
                      • Dec 2019
                      • 14147
                      • Canada

                      #30
                      I2C_SNS1_S0_SCL - 1,6V
                      I2C_SNS1_S0_SDA - 1,6V
                      Confirm that these lines are not @ 1v8 like the others?

                      Remove all power. Meter in diode mode. Red meter probe to ground; black meter probe to:

                      I2C_SNS1_S0_SCL ; what is the diode mode reading?
                      I2C_SNS1_S0_SDA ; what is the diode mode reading?

                      Comment

                      • hopkok
                        Senior Member
                        • Oct 2014
                        • 178
                        • Slovakia

                        #31
                        I am sure, they were 1v6. I can change bateries in multimeter and repeat measurement+ make diode mode reading. That voltage shoud be 1v8? Maybe faulty trackpad? Trackpad cable?

                        Comment

                        • mon2
                          Badcaps Legend
                          • Dec 2019
                          • 14147
                          • Canada

                          #32
                          To me it sounds lower than the norm. Someone is pulling these lines down. Not sure if it impacts the raised fault but the default parked voltage should be 1v8. Sure - disconnect what you can and attempt to test this line again.

                          There appears to be only thermal sensors on this dedicated SMBUS network.

                          Click image for larger version

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                          Comment

                          • hopkok
                            Senior Member
                            • Oct 2014
                            • 178
                            • Slovakia

                            #33
                            Hi, I double check it, 1v6 voltage there on both lines, everything disconnected from the board.
                            Diode mode reading.
                            I2C_SNS1_S0_SCL ; 0,4v
                            I2C_SNS1_S0_SDA ; 0,4v


                            Edit: I probably found culprit. C5850 area damaged
                            Attached Files

                            Comment

                            • hopkok
                              Senior Member
                              • Oct 2014
                              • 178
                              • Slovakia

                              #34
                              Its solved my friend. You helped me a lot. Thank you.
                              Attached Files

                              Comment

                              • obelix24
                                Badcaps Veteran
                                • Jun 2023
                                • 291
                                • Slovakia

                                #35
                                I've returned to this macbook and 3 ports are working 20V ... One port was taking only 5V and 0,2A
                                I've tried to replace CD3215 for this port 3x and still the same issue ... but now it's not turning on ampmeter on this port at all, on other ports still 20V but macbook doesn't turn on (no chime, anything)

                                I found out that i can't measure resistance to ground on PP20V_USBC_TA_VBUS (on other port's i'm getting correct value) here it's only trying my multimeter is no able to get value ...

                                I tried to remove everything from that line PP20V_USBC_TA_VBUS
                                QB300 - result the same
                                FB200 - result the same
                                DB501 - result the same
                                DB500 - result the same
                                CB510 - result the same
                                CB511 - result the same
                                CB301 - result the same
                                UB300 - result the same

                                any idea ?
                                Last edited by obelix24; 03-04-2024, 01:40 AM.

                                Comment

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