DV 2500/DV2000 SE Will not P.O.S.T./No Power

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HP DV 2500 14.1"
Intel Dual Core - Dead


DV2500 model number  and of the DV2000 Special Edition series that exhibits power problems. The indication of power problems were shown by the ring-light on the DC Jack. Since the LED uses the +5v line this points to a problem in the low power section of the unit. There were no other symptoms other than not powering on, or rapidly shutting down.


Sections also controlled by the +5v

  •  Power ON Button
  •  LED's and panels
  •  DC Jack Power indicator (ring light)



After close examination, found that the USB port was shorted.  This was a clear visual short. PIN 1 is +5v for the USB which is Vcc or 5v for powering device that is plugged into port.  With a dead short the power controller (usually a MAXIM IC) will not allow the rest of the unit to turn on. Though making troubleshooting a little more challenging, it protects the motherboard from additional damage as well as other parts.


Steps taken:
Remove damaged USB port
Clean solder holes
Replace USB port
Test
Reassemble
Test Again.

Comments

  1. mattbrad2Fri Feb 04, 09:48:00 PM EST

    Can't say how many times I have desktops not power on because of this. Amazing that people can break these ports. I mean, how hard to you have to jam a USB stick on there backward for that to break like that?

    ReplyDelete
  2. asifnawazSat Feb 05, 03:02:00 AM EST

    This means that the USB port it self is damage and shorting the volts supplying from it MAXIM power contol IC.and when voltage reachs to pin 1 then that IC can't return some sort of voltage reach indication and when this happen the IC (power controll ic) shutdown complete unit.Am i right in my theory?

    ReplyDelete
  3. HoosierSat Feb 05, 11:35:00 AM EST

    Asifnawaz: Correct
    Circuit protection keeps the laptop from starting a fire, or killing more parts when there is a short.

    MattBrad2: I'm just surprised how many people don't know that is not a 'Push as hard as you can' port. The small plastic tang is a keyway and you cannot force it. But anyway its a living knowing how to replace it. Let me see if I can find the video I made to remove the port.

    ReplyDelete
  4. michaelFri Feb 11, 05:45:00 AM EST

    Brilliant, i have just had one in and couldnt work it out and was looking through your fixes and bingo its fixed-up and running now

    ReplyDelete
  5. HoosierSun Feb 13, 10:00:00 AM EST

    Michael: Glad you got it solved

    ReplyDelete

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I cannot repair laptops for you via the internet, I can only answer questions related to posts. This is because I have not had experience on every motherboard that is out there. Bear with me.

If you do need it repaired. Contact me for quote (US/CDN Only)

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