Troubleshooting: Lenovo Motherboard

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  • kiraro
    Senior Member
    • Jan 2016
    • 177
    • North NY

    #81
    Re: Troubleshooting: Lenovo Motherboard

    that very low value for +1,35v line , check pq501 and pq502

    Comment

    • DanFen
      Badcaps Veteran
      • Apr 2017
      • 201
      • Malta

      #82
      Re: Troubleshooting: Lenovo Motherboard

      I have a hard time testing these mosfets Resistance measurement keeps increasing forever or keeps decreasing forever or else it just changes value like crazy (since I have it set on auto range, sometimes it even switches between kohms and mohms). Can't understand why this happens. Maybe I'm just doing something wrong.

      I am just trying to follow this. Is this the correct way or am I getting crazy?

      1. Black on Source and Red on Drain
      2. Red to Gate momentarily
      3. Black on Source and Red on Drain

      EDIT: Probably red should be on source (checked the diode symbol here)

      In the meantime I've measured the voltage:

      PQ501:
      D > 19V
      S > 0V

      PQ502:
      D > 0V
      S > 0V
      Last edited by DanFen; 03-18-2020, 10:25 AM.

      Comment

      • kiraro
        Senior Member
        • Jan 2016
        • 177
        • North NY

        #83
        Re: Troubleshooting: Lenovo Motherboard

        when power on check +3VALW_SOC (Q26 pin1 -Drain) +1.0VALW (PJ702) +1.8VALW (pj602) VR_+1.0VALW_PWRGD (pin 5 of PU701 )
        and SYSON signal on PU501 pin 16 (S5)

        with simplicity :
        N-channel : (diode mode)
        1-red (source),black(drain) 0500~0600
        2-black(source),red(drain) Open
        3-and test if source and gate short together or not
        P-channel : (diode mode)
        1-red (drain),black(source) 0500~0600
        2-black(drain),red(source) Open
        3-and test if source and gate short together or not
        Last edited by kiraro; 03-18-2020, 01:49 PM.

        Comment

        • DanFen
          Badcaps Veteran
          • Apr 2017
          • 201
          • Malta

          #84
          Re: Troubleshooting: Lenovo Motherboard

          Thanks for the clarification

          +3VALW_SOC (Q26 pin 1 - Drain) = 3.3V
          +1.0VALW (PJ702) = 1V
          +1.8VALW (PJ602) = 1.8V
          VR+1.0VALW_PWRGD (PU701 pin 5) = 3.3V
          SYSON signal on PU501 pin 16 (S5) = 0V

          PQ501 (n):
          Source (red) to Drain (black) = 0.554
          Source (black) to Drain (red) = 2.9
          no cont between gate and source

          PQ502 (n):
          Source (red) to Drain (black) = 0.08
          Source (black) to Drain (red) = 0.370
          no cont between gate and source

          Originally posted by kiraro
          when power on check +3VALW_SOC (Q26 pin1 -Drain) +1.0VALW (PJ702) +1.8VALW (pj602) VR_+1.0VALW_PWRGD (pin 5 of PU701 )
          and SYSON signal on PU501 pin 16 (S5)

          with simplicity :
          N-channel : 1-red (source),black(drain) 0500~0600
          2-black(source),red(drain) Open
          3-and test if source and gate short together or not
          P-channel : 1-red (drain),black(source) 0500~0600
          2-black(drain),red(source) Open
          3-and test if source and gate short together or not
          Last edited by DanFen; 03-18-2020, 03:11 PM.

          Comment

          • kiraro
            Senior Member
            • Jan 2016
            • 177
            • North NY

            #85
            Re: Troubleshooting: Lenovo Motherboard

            check pj201 +20VSB (pin1 PQ210)

            Comment

            • DanFen
              Badcaps Veteran
              • Apr 2017
              • 201
              • Malta

              #86
              Re: Troubleshooting: Lenovo Motherboard

              19v

              Originally posted by kiraro
              check pj201 +20vsb (pin1 pq210)

              Comment

              • lapfix
                Badcaps Legend
                • Mar 2020
                • 2715
                • my workshop

                #87
                Re: Troubleshooting: Lenovo Motherboard

                Syson and susp# are the enable signals for PU501.
                Syson enable Pu501 to generated 1.35V. Susp#enable Pu501 to generated 0.675V.
                In the power sequence , before this steps (suson and susp#) we have to check PM_SLP_S3# and PM_SLP_S4# at UE1 pin 18 and 21.

                Comment

                • kiraro
                  Senior Member
                  • Jan 2016
                  • 177
                  • North NY

                  #88
                  Re: Troubleshooting: Lenovo Motherboard

                  - UE1 Pin93 EC_RSMRST#
                  -all pins voltage QC11 and QC12
                  Last edited by kiraro; 03-20-2020, 05:22 AM.

                  Comment

                  • DanFen
                    Badcaps Veteran
                    • Apr 2017
                    • 201
                    • Malta

                    #89
                    Re: Troubleshooting: Lenovo Motherboard

                    UE1
                    Pin 93 (EC_RSMRST#) = 3.3V

                    QC11
                    Pin 1 = 0V
                    Pin 2 = 1.7V
                    Pin 3 = 0V
                    Pin 4 = 0V
                    Pin 5 = 1.7V
                    Pin 6 = 0V

                    QC12
                    Pin 1 = 0V
                    Pin 2 = 1.7V
                    Pin 3 = 3.3V
                    Pin 4 = 1.7V
                    Pin 5 = 1.7V
                    Pin 6 = 0V

                    Originally posted by kiraro
                    - UE1 Pin93 EC_RSMRST#
                    -all pins voltage QC11 and QC12

                    Comment

                    • DanFen
                      Badcaps Veteran
                      • Apr 2017
                      • 201
                      • Malta

                      #90
                      Re: Troubleshooting: Lenovo Motherboard

                      Those are both 0V

                      Originally posted by lapfix
                      Syson and susp# are the enable signals for PU501.
                      Syson enable Pu501 to generated 1.35V. Susp#enable Pu501 to generated 0.675V.
                      In the power sequence , before this steps (suson and susp#) we have to check PM_SLP_S3# and PM_SLP_S4# at UE1 pin 18 and 21.

                      Comment

                      • lapfix
                        Badcaps Legend
                        • Mar 2020
                        • 2715
                        • my workshop

                        #91
                        Re: Troubleshooting: Lenovo Motherboard

                        It seems that your S3 state won't be complete ,did PU501 get hot ! try to use a good known ram (DDRL)
                        What's the voltage on pin 12 !
                        Try to flash your bios .

                        Comment

                        • DanFen
                          Badcaps Veteran
                          • Apr 2017
                          • 201
                          • Malta

                          #92
                          Re: Troubleshooting: Lenovo Motherboard

                          No it's not hot. Voltage on Pin 12 of PU501 is 5V.

                          EDIT: Tried good known RAM and still the same. It turns on, and turns off after ~2 sec. There's a click when it turns off. I also don't have the tool to flash the BIOS chip.

                          Originally posted by lapfix
                          It seems that your S3 state won't be complete ,did PU501 get hot ! try to use a good known ram (DDRL)
                          What's the voltage on pin 12 !
                          Try to flash your bios .
                          Last edited by DanFen; 03-22-2020, 05:35 AM.

                          Comment

                          • DanFen
                            Badcaps Veteran
                            • Apr 2017
                            • 201
                            • Malta

                            #93
                            Re: Troubleshooting: Lenovo Motherboard

                            In such case, since it's not a high end motherboard, I think it makes more sense to simply order another one.

                            Just want to thank all of you guys who supported me with this, I definitely learnt some new stuff

                            Comment

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