Toshiba A75 - No picture on screen.

TOSHIBA A75 series are workhorses they will run and run.  The only problems I have experienced with this model  that is fairly common is the DC Jack fails, Overheating and onboard memory failure.

Since onboard memory can cause the above symptom, that was on of the first things I tested. The memory turns out to be fine. Opening the unit I see that there had been a previous spill that had dried and and was on some important VLSI chips. The next step was to closely inspect the spots where the spill was and visually determine if it could be the cause of failure.  This depends on whether it was on any PCI or video subsystems.  As it turns out it was on the PCI subsystem.

Comments

  1. michaelFri May 20, 11:25:00 AM EDT

    Hi Mayo, When i have a spill on an motherboard and it needs to be cleaned i remove the Bios battery and wash the mobo with distilled water and then clean with alcohol, is this the right order to do it in or is it completly wrong.
    Thanks, Mike

    ReplyDelete
  2. HoosierFri May 20, 03:45:00 PM EDT

    Actually the water should be boiling hot! Then rince with alcohol and let sun dry or oven dry at 200F, for about a half hour. When water is at room temp, it will not remove coffee, sugar, and cream type spills. Sugar in the beverages is the most difficult to disolve. So Hot water does fix most of them. But also, if the unit was on (as usually is) it can short other areas.

    ReplyDelete
  3. jannySat May 21, 01:40:00 AM EDT

    This comment has been removed by a blog administrator.

    ReplyDelete
  4. naphMon Jun 13, 01:57:00 AM EDT

    hi Mayo,

    i have problems with Acer Aspire 2920z,
    when i pressed power on button, all LED indicators is running up like normal.
    But there is no images send to LCD panel or external monitor

    i have rewrite BIOS firmware (usually work fine) ... but the problems still same

    please, give me some advice

    thanks Mayo, keep useful posting at this blog ... i like it, very helpfull

    ReplyDelete
  5. HoosierWed Jun 15, 07:39:00 AM EDT

    Sorry Naph, not totally familiar with the model but I think that is a 14.1 nVidia based board. An nVidia reflow should be able to resolve that problem.

    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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