Wednesday, February 16, 2011

Dell XPS No Video

This Dell XPS comes in with 2 others, so after months of none, now three in one day. Various issues and  different problems.


Shift-Click to see larger image
The first one has a pink shell. Exact model number not copied yet. It has no video but starts like it will go into P.O.S.T. but never does.  The LCD don't not light, or flash briefly (which indicates the inverter works). Removing the keyboard and top I noticed this burnt plastic mark next to one of the connectors for the LCD.  


With motherboard removed, the plastic cover was slowly removed and noticed a coil with pads damaged so there was no electrical path completed. Removing the damaged coil and cleaning the area, required me to also remove a few mm of laquer from the mobo.  This exposes copper which will become the 'new' pad completing the circuit.


Test and backlight and video appears on LCD. So the problem was an open path by blown coil.  

6 comments:

  1. I'm always apprehensive upon finding such shorted/burnt components. They didn't burn up for no reason at all, yet simply replacing it fixed the problem. Curious.

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  2. I agree, Larry. I've wondered the same thing however isn't this the same with a random shorted cap or fet? Shoddy wave soldering perhaps? In many cases, I've found it can be traced back to (drum roll) the user. They ended up doing something, well.. stupid, that lead to the problem. After all, most DC jack problems didn't just wiggle themselves free on their own.

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  3. Yeah, DC jacks I can understand because of the mangling and abuse they take (partly attributable to their sticking out like a sore thumb, inviting a sideways knock). But what could a user possibly do to burn that coil, or a cap or MOSFETs? I wonder if it isn't loose solder balls/debris that have caused a short then moved along like a lost sock. As I said, I find it curious.

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  4. I've had customers try to "clean the inside" of their laptop, spill God knows what inside of it and let their cat sleep on the keyboard. Don't even get me started on the bugs found inside of them. I can't tell you the amount of times I've had to use gloves to take one apart.

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  5. Larry: Actually when cheap parts are used, nothing has to cause the failure. You can eventually shoot yourself in the foot trying to save 3 cents on a part (multiplied by millions). HP has lowered their specs to the point of No-Name companies such as KOBY, and other dollar store electronics. And let the manufacturers put anything in them to save pennies. The G50-G62 models are worse than E-Machines and Everex.

    MattBrad: agreed, I used to operate a wave solder once during my 'training' period. Now with the new RoHS, and waterbased flux operators and managers just want stuff out! Counting numbers produced without regard to failure rates. You know 99% of the electronics I see today would have never passed my training standards that NASA/AF specs taught.

    Glad the space program is not outsourcing.

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  6. Also this:
    The Dell Inspiron 1501 fails because of a coil near the DC Jack. The thin copper foil cannot carry the current. So one side of the coil develops an arc, and continued plugging in and removal makes the arc eat copper. Eventually there is no contact. Also the coil actually split linearly.

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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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