DV7 No POST & Blinking Lights

This unit was thought to be a reflow and previous user or store overheats parts. So this cap that was to be seated on the South Bridge was sitting on the edge of it. Totally out of place. That is the primary reason I always look closely at the motherboard before attempting repairs. Parts get old, solder gets weak.



Comments

  1. nando754Sun Jul 01, 04:33:00 PM EDT

    I have a dv4 with blinking lights. I took out the motherboard to check it out. while I was checking out to see what was the problem. I booted up the motherboard out of its case I noticed that the ic chip on the bottom corner where the SD card reader is, On the side where the CPU and GPU are, Got super hot really fast. Do you think that I should replace it? Or how can I test to see if that is the only problem. I have reflowed dozens of this laptops before with success.

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    Replies
    1. HoosierTue Jul 03, 09:54:00 AM EDT

      Nando: You didn't say what chip number or type was. Check to see if the chip is shorted first (in circuit) sometimes a bypass cap could be shorted, and instead of filtering to ground is shorting to ground. Check the ceramic caps and the mosfet with meter in diode mode.

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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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