Lenovo NM-C861 backlight issue

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  • rookieme
    Badcaps Veteran
    • Oct 2014
    • 396
    • Greece
    #1

    Lenovo NM-C861 backlight issue

    Hello,
    the mainboard at first booted only sometimes with memory error.
    After ram rework it boots fine but the new issue is no backlight.
    Display did not had any issue so I guess something from the motherboard.
    At the JEDP1 I have 19V at pins 1 & 2, DISPOFF# at pin 15 is 0V and INVT_PWM at pin 16 is 2,82V.
    Same values are with lid closed.
    Lid switch works ok when tested with windows software.
    Is there something else I'm missing?
    Tags: None
    • rogfanther
      Badcaps Veteran
      • Jul 2006
      • 458
      • Brazil
      #2
      I believe DISPOFF# should not be low . But wait for other opinions also.

        Comment

        • Bonzas
          Badcaps Veteran
          • Jan 2018
          • 470
          • Indonesia
          #3
          you forget pin 18 & 19 ?

            Comment

            • rookieme
              Badcaps Veteran
              • Oct 2014
              • 396
              • Greece
              #4
              Originally posted by Bonzas
              you forget pin 18 & 19 ?
              +LCDVDD_CON [pins 18& 19] has 3,34V and I'm getting signal at display, backlight is missing

                Comment

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