Announcement

Collapse
No announcement yet.

Lenovo Legion 5 Pro - NM-D601 REV1.0 Turns off with battery conected

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

    #21
    Originally posted by mon2 View Post
    Can you confirm the gate voltage of PQ5407 WITH battery & power adapter? It does not look right.

    Click image for larger versionName:	gate_voltage.pngViews:	0Size:	50.3 KBID:	3306120

    A few other points:

    1) remove all power -> measure the resistance of the 4k resistor @ PR5405. Confirm this resistor matches the schematic value of 4k. Concern is that in your measurements, the CMSRC voltage to ground is lower than the power adapter voltage.

    2) double check the BATTERY only measurement for pins 1 & 2 on the charger IC.

    3) repeat the measurements WITH BATTERY & power adapter for pins 1 & 2 on the charger IC. Pin # 2 (ACP) should be a higher voltage than pin # 1 (ACN). In either case, the voltage measurements should be very close to each other. Note the voltage drop across ACP and ACN junction when using only the power adapter. Higher voltage difference when the battery is used or when both battery & power adapter is used.

    With no power to the board and no battery, confirm the resistance from pin # 2 (ACP) directly on the charger IC to the current sense resistor @ PR5401. Then repeat the same test with pin # 1 to the same current sense resistor. Both checks should be ~0 ohms. Touch your meter probes together and this is the same resistance measurement you should have for this current sense resistor path.

    Also, I think that for the BATTERY only, the pin # 19 measurement was missed in the above table. It should be the same voltage as pin # 20.
    Rectify the voltages on pin 23 gate of PQ5407 and it is still 0.5 with battery+charger, rectify the battery and charger alone and it is still 0V.

    Rectify measurement in PR5405 and it is 3.99Kohms

    Rectify measurement on pins 1 and 2 only with battery connected, they remain at 15.5 on both pins
    -battery+charger 20.4 on both pins 1 and 2

    measurement pin 1 and 2 with respect to PR5401 in both cases was 0.6 ohms

    I correct the measurement on pin 19 only with 15.74V battery pin 19 and 20

    Comment


      #22
      Originally posted by mon2 View Post
      Can you confirm the gate voltage of PQ5407 WITH battery & power adapter? It does not look right.

      Click image for larger versionName:	gate_voltage.pngViews:	0Size:	50.3 KBID:	3306120

      A few other points:

      1) remove all power -> measure the resistance of the 4k resistor @ PR5405. Confirm this resistor matches the schematic value of 4k. Concern is that in your measurements, the CMSRC voltage to ground is lower than the power adapter voltage.

      2) double check the BATTERY only measurement for pins 1 & 2 on the charger IC.

      3) repeat the measurements WITH BATTERY & power adapter for pins 1 & 2 on the charger IC. Pin # 2 (ACP) should be a higher voltage than pin # 1 (ACN). In either case, the voltage measurements should be very close to each other. Note the voltage drop across ACP and ACN junction when using only the power adapter. Higher voltage difference when the battery is used or when both battery & power adapter is used.

      With no power to the board and no battery, confirm the resistance from pin # 2 (ACP) directly on the charger IC to the current sense resistor @ PR5401. Then repeat the same test with pin # 1 to the same current sense resistor. Both checks should be ~0 ohms. Touch your meter probes together and this is the same resistance measurement you should have for this current sense resistor path.

      Also, I think that for the BATTERY only, the pin # 19 measurement was missed in the above table. It should be the same voltage as pin # 20.


      Update: bought a small oscilloscope to take the reading of pin 23 for PQ5407 attached a photo

      I did the readings with and without battery and the result was 0
      Attached Files

      Comment


        #23
        Update 2:

        Check the measurements regarding this video
        (https://www.youtube.com/watch?v=ODcc...LaV0BS&index=7) in diode mode and everything is fine except PIN 17 with a value in the video of 0.6622 and on my motherboard it is 0.501. It is the only difference I noticed, everything else is fine with respect to ground (RED ground, BLACK to the IC pins)

        Or what oscilloscope measurements can I take?

        Comment


          #24
          As suggested by mcplslg123 , test with a known good battery. You can buy from Amazon and return it if not required. The issue may be with the battery itself (deep discharged state and is now locked or similar).

          Comment


            #25
            Originally posted by mon2 View Post
            As suggested by mcplslg123 , test with a known good battery. You can buy from Amazon and return it if not required. The issue may be with the battery itself (deep discharged state and is now locked or similar).
            Thanks, that's what I'll do and order a new compatible replacement battery and I'll do the test. I will update the post with the result

            Comment

            Working...
            X