Hp 15 la-d707p not power on .

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  • lapfix
    Badcaps Legend
    • Mar 2020
    • 2635
    • my workshop

    #21
    Re: Hp 15 la-d707p not power on .

    Sorry to be late.

    Yes there's no short to GND , so a leaky component is most likely

    Test of all coils with Diode mode / Resistance mode :

    PR 203 = 0.433v /
    Pl8 = 0.508v / not stable start from 10.70mohm than decrease
    Pl9 = 0.345v / not stable start from 540.1 kohm than decrease
    Pl11 = 0.234v / 330 ohm
    Plv2 = 0.014v / 10 ohm
    Plv3 = 0.014v / 13.5 ohm
    Plw1 = 0.097v / 72 ohm
    Pl 15 = 0.408v / 29.43 ohm
    Pl 602 = 0.089v / 46.6 ohm
    Pl 1206 = 0.026v / 18.4 ohm
    Pl 1203 = 0.010v / 9.9 ohm
    Pl 1205 =0.012v / 11.4 ohm

    ACN (1) / ACP (2) reach the current sense resistor = yes

    Comment

    • mon2
      Badcaps Legend
      • Dec 2019
      • 13887
      • Canada

      #22
      Re: Hp 15 la-d707p not power on .

      Remove all power -> meter in resistance mode -> measure the resistance to ground of +19.5VB.

      What is the measurement?
      Attached Files

      Comment

      • lapfix
        Badcaps Legend
        • Mar 2020
        • 2635
        • my workshop

        #23
        Re: Hp 15 la-d707p not power on .

        6.812 mohm ...b ut not stable it decrease

        Comment

        • mon2
          Badcaps Legend
          • Dec 2019
          • 13887
          • Canada

          #24
          Re: Hp 15 la-d707p not power on .

          That is a very high resistance.

          Can you post a picture of your meter with the scale being used for the resistance measurements?

          When you short the meter probes, do you see ~0 ohms on the meter?

          Comment

          • lapfix
            Badcaps Legend
            • Mar 2020
            • 2635
            • my workshop

            #25
            Re: Hp 15 la-d707p not power on .

            the scale is automatic , short the meter probes 000.7 ohm.

            maybe i must focus more at all jumpers !!..something is blocking pu201 to accomplish his rule..

            Comment

            • mon2
              Badcaps Legend
              • Dec 2019
              • 13887
              • Canada

              #26
              Re: Hp 15 la-d707p not power on .

              Can you confirm the following ?

              1) If you remove pq203 and apply a DC power supply onto the main power rail - the logic board works fine ? You also see the ~24v on the ACDRV pin of the charger IC ? (after you remove PQ203)

              2) if yes, replace pq203 (even though the readings are good with the meter) and test again.

              3) if the fault remains, replace the charger IC and test again.

              It is the charger IC that is responsible to drive the ACDRV pin and respectively, creates the boosted gate voltage. Also monitors the current draw on the local rails (main & battery charge) to enable / disable ACDRV.

              It is vital to inspect that the current sense circuit is operational and all parts are present to the charger IC. After this review, consider to replace the charger IC and test again.

              Update this thread as your proceed.

              Comment

              • mcplslg123
                Badcaps Legend
                • Jun 2015
                • 7262
                • india

                #27
                Re: Hp 15 la-d707p not power on .

                Originally posted by mcplslg123
                Try replacing PC208/209/210 with exact same value.
                Did you acted on this??

                Comment

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