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820-2530 ppbus .19 volts always stays green

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  • #31
    If you get correct voltage at F7000, shouldn't have other reason.
    However, check Q7020 and C7025.


    • #32
      I am still waiting on my ISLs to ship. Just curious, my oversized replacement for d7010 only drops 4/100ths of a volt, 18.50 to 18.46, is that normal? I was expecting more like 4/10ths of a volt drop. Could this cause any issues?

      also will any ISL6258AHRTZ work? I see some have a second group of letters besides this main listing
      Last edited by shanenin; 02-20-2019, 07:03 PM.


      • #33
        I replaced both d7010 and u7000 and I do now have a good ppbus of 12.6. For what it is worth, the charger always stays green and does not go to orange.

        I do not have any voltage on pm_slp_s4

        I was looking at u7750 and some stuff does not seem right. I would expect 1volt on both pins 2 and 3, but I have 3.4 volts on both, is that suspect? I have only .8 volts on pin 6.


        • #34
          Wrong assumptions.
          Do you get 1.05V at C7771?
          If not, change that cap...

          PM_SLP_S4_L should go high when press power button.


          • #35
            why would I not assume based on the names P1V05_S5_EN would be 1.05 volts and P1V05_S5_PGOOD is also 1.05 volts? I am asking to try and learn and understand


            • #36
              Originally posted by 2informaticos View Post

              PM_SLP_S4_L should go high when press power button.
              when I start it by attaching the magsafe it is not pulsing.

              I think I have checked all of my s5 rails, but this older board seems different than I am used to and it does not seem to have many listed in the schematic
              Last edited by shanenin; 02-28-2019, 12:09 PM.


              • #37
                MCP platforms never start when charger is plugged in; another wrong assumption.
                Only iCore boards start this way.

                "why would I not assume based on the names"
                Just for that; pay atention to ENTIRE name.
                EN and PGOOD mean something; they are signals, not power rails...


                • #38
                  Thanks for taking the time to explain these things. I did know they were signals, but I see my mistake. The name was referring to the power rail it started, not the voltage of the signal.

                  I attached a wire to pin5 of the keyboard connector and tapped the other side to ground to mimic pressing the button, but I am not getting any pulse on pm_slp_s4. Was that a correct way of starting the system?

                  Could I also short smc_onoff_l to start it?


                  • #39
                    Solder a wire on SMC_ONOFF_L line and touch the ground (momentary).

                    "Do you get 1.05V at C7771?
                    If not, change that cap..."
                    Can we get a reply?


                    • #40
                      we do have 1.05v at c7771. I was looking for a clock chip and realized that is part of the MCPs job. I did check for a frequency at rtc_clk32k_xtalin and out and I get an erratic reading between 31 and 36mhz (jumping)

                      I am not getting any pulse on pm_slp_l when touching smc_onoff_l to ground


                      • #41
                        Post resistance to ground (ohm scale) at 3V42 power rail.
                        You must get more than 30K...


                        • #42
                          Yeah agreed less than 30Kohms this junk


                          • #43
                            I will test this later. Why are we checking for less than 30k on pp3v42 ? What does that indicate? I am guessing bad mcp, if so why?


                            • #44
                              Yes, lower value denotes bad MCP...


                              • #45
                                Thanks 2informaticos for your patience and help :-)

                                on a side note,any idea what would damage the MCP?

                                (I have not yet verified thst is the problem, but that uneven frequency seems bad)
                                Last edited by shanenin; 02-28-2019, 09:55 PM.


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