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    HP Probook 640 G2 dead

    i guys
    I got this HP Probook 640 G2, it is completely dead, no power, no LEDs, no fan nothing

    The 19V PSU is OK and there is 19V present at the power connector on the motherboard.

    I disconnected everything from the motherboard but it makes no difference, I thought the fan may spin for an instance when power is first connected to the laptop.

    The four way ribbon from the power button PCB to the mainboard checks OK for continuity. Should there be a standby voltage on this ribbon with the PSU connected?

    Does anyone have a schematic for the motherboard (google was not my friend) or any other suggestion how to diagnose the fault.

    Thanks
    Richard
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    #2
    Re: HP Probook 640 G2 dead

    Motherboard is Inventec Circus 6050A2723701-MB-A02 . No schematics (or any other info) available apparently.
    You should get 3.3V on the power button. The motherboard will not turn on by itself, you need to press the power button or short the pads on the board.

    PS: I had one die on me, it was still under warranty though. I suspect the PCH, but this may not be your issue.
    OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

    Comment


      #3
      Re: HP Probook 640 G2 dead

      If the front power light does not turn on to indicate battery charge status with the AC adapter and battery connected, then it must be failing very early in the power sequence.

      You may measure the grey coils/inductors to see if you are getting the 3.3V and 5V power rails on 2 of them. If not, then measure the pins on the input FETs and charging IC. Those are located on the top side of the board near the power jack. Also, posting a clear picture of that area with legible labels and chip numbers would be useful if you need help in diagnosing an issue in that area.

      And it's always a good idea to thoroughly examine the board for visibly marked/damaged or hot components.

      Comment


        #4
        Re: HP Probook 640 G2 dead

        I had the same problem with a 640 g2, and replace this mosfet near of the power jack... good look
        https://ibb.co/fn9nKd

        Comment


          #5
          Re: HP Probook 640 G2 dead

          Might be too late but I replaced q60001 near the DC socket and boom. Working.

          Comment


            #6
            Re: HP Probook 640 G2 dead

            friend, where did you get that mosfet, or does anyone else know where to get it?

            Comment


              #7
              Re: HP Probook 640 G2 dead

              Originally posted by sickz View Post
              friend, where did you get that mosfet, or does anyone else know where to get it?
              u dont need exact chip. u just need mosfet with right channel and some max current

              Comment


                #8
                Re: HP Probook 640 G2 dead

                Originally posted by ktmmotocross View Post
                u dont need exact chip. u just need mosfet with right channel and some max current
                Hi all,
                I have a 640 G2, with the MOSFET at 060010 gone bad (19.5V in, but 0V out from any of the 4 pins on the other side). You've probably realised by my wording that I am no electronics guru! I know enough to know that is not good and am fairly good at swapping board chips

                On my board the MOSFET is an N-Channel Magnachip MDU1515URH, rated 30V and 20.8A.

                I would like to call upon anyone more experienced than me to ask, what chip can I replace this with? Can I exceed the Voltage? Can I exceed the rated amps? What are the risks?

                I need to buy a replacement from the UK, but can only find MDU1515URH from China (6-week wait!).

                I noted another poster showed his bad MOSFET and it was marked 8888 (is that an FDMS8888?). This is rated 30V maximum drain source voltage and 21A maximum drain current. Again, these are only available from China!

                If anybody can help me find a compatible chip which is available on UK ebay, I would be most grateful.

                Thanks

                Comment


                  #9
                  Re: HP Probook 640 G2 dead

                  MDU1515URH is a N channel fet and AON6414A will do as replacement.

                  Comment


                    #10
                    Re: HP Probook 640 G2 dead

                    Originally posted by dicky96 View Post
                    i guys
                    I got this HP Probook 640 G2, it is completely dead, no power, no LEDs, no fan nothing

                    The 19V PSU is OK and there is 19V present at the power connector on the motherboard.

                    I disconnected everything from the motherboard but it makes no difference, I thought the fan may spin for an instance when power is first connected to the laptop.

                    The four way ribbon from the power button PCB to the mainboard checks OK for continuity. Should there be a standby voltage on this ribbon with the PSU connected?

                    Does anyone have a schematic for the motherboard (google was not my friend) or any other suggestion how to diagnose the fault.

                    Thanks
                    Richard
                    you need to check all the power rail and power sequence.. start with vin 19v then b+ if there is no b+ 5v ALW and 3.3V alw will not be present did you see led lights when you connect the charger? check all voltages that you can measure and post it here...
                    Never stop LEARNING because life never stops TEACHING!

                    Comment


                      #11
                      Re: HP Probook 640 G2 dead

                      i have Hp 640 g2 and powers-on after I programmed the bios and the fan speed is high and the processor is not warm, what do you suggest is the cause?

                      Comment


                        #12
                        Re: HP Probook 640 G2 dead

                        Originally posted by nik nik View Post
                        i have Hp 640 g2 and powers-on after I programmed the bios and the fan speed is high and the processor is not warm, what do you suggest is the cause?
                        I suggest that you read this thread first - https://www.badcaps.net/forum/showthread.php?t=88758
                        Then read post #10 of this thread.With no voltage measurements nobody can help you .
                        All donations to badcaps are welcome, click on this link to donate. Thanks to all supporters

                        Comment


                          #13
                          Re: HP Probook 640 G2 dead

                          I just got this laptop and it will not power on.
                          Power supply is good.

                          Can somebody let me know where some test points are?
                          I do have 20vdc at the 4R7 resistor next to the power plug.

                          The symptom is that the laptop will not power on.
                          Get just 1 flash on keyboard.. power Key and speaker wifi.

                          Its not battery or charger..
                          Tried it with battery and without battery.

                          will not boot up with Windows and B key plugged in without battery.

                          So.. i pulled the motherboard to have a look. I dont see physically anything wrong..

                          Not sure if its power issue or Bios issue.
                          Attached Files
                          Last edited by Rockton; 03-12-2021, 01:16 AM.

                          Comment


                            #14
                            Re: HP Probook 640 G2 dead

                            Pad 60800 has 1v.
                            Pad 60810 has 20v.
                            Pad 60500 has 0v.
                            Pad 60510 has 20v.
                            Pad 61410 has 20v.
                            Pad 61400 has 0v.
                            Pad 60011 has 20v.
                            On flip side of board:
                            Pad 1411 has 3.3v.
                            Pad 7100 has 1v.
                            Pad 4500 has 1v.
                            Pad 300 has 3.3v.
                            Pad 310 has 0v.
                            Pad 7005 has 5.25v.
                            Pad 7004 has 0v.
                            Pad 7002 has 0v.
                            Pad 7001 has 3.3v.
                            Pad 7000 has 3.3v.
                            Pad 7002 has 5.25v.
                            Pad 60210 has 20v.
                            Pad 60200 has 5.25v.
                            Pad 60110 has 5.25v.
                            Pad RTC60100 has 3.3v.

                            Comment


                              #15
                              Re: HP Probook 640 G2 dead

                              Picture of both sides of MB
                              Attached Files
                              Last edited by Rockton; 03-12-2021, 01:41 AM.

                              Comment


                                #16
                                Re: HP Probook 640 G2 dead

                                060010 Mofset MDU1515 Has 20vdc on every pin except pin 4 which as 26 VDC

                                Comment


                                  #17
                                  Re: HP Probook 640 G2 dead

                                  if it is dc-in mosfet, pin4 is supposed to be close to 25V. So no issue there.

                                  Comment


                                    #18
                                    Re: HP Probook 640 G2 dead

                                    Pin 4 is the gate voltage so I assume it’s going to some power control chip. . I am guessing that this mosfet is there just in case you plug in a power supply that’s not Center positive.


                                    I am curious about the 1 volt Pads.
                                    Last edited by Rockton; 03-12-2021, 02:13 PM.

                                    Comment


                                      #19
                                      Re: HP Probook 640 G2 dead

                                      It goes to your charging Ic.

                                      Comment


                                        #20
                                        Re: HP Probook 640 G2 dead

                                        Ok. I figure the 1vdc goes to the CPU.
                                        So, I think my power to the MB should be ok as I got all the voltages.

                                        Therefore.. my problem might be in the startup chip or bios area?

                                        Comment

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