Replaced all video components, still not working

natarshia

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Jan 3, 2012
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18,510
Hello,
A students toshiba l305 was dropped and the screen stopped working but was not cracked.
If connected to external monitor it worked, but i did not see anything , even witha flashlight on the lcd. I purchased new backlite and tested it before installing. It did not work, i had 2 new ones and they both didn't work. So then I replaced inverter, no luck, and finally the lcd cable, still no luck. So if I have all three new components hooked up not in the lcd, shouldn't the bulb at least turn on. I tried FN F5 to see if it would force it on , but no luck. Any clues or general advice on if it's just dead would help.

thx
 
Solution
Sounds like you already put more into troubleshooting than most of us here would have. Kudos.
At this point I am not sure if it is cost-effective to replace more parts to it vs. using it with an external monitor, as a small desktop replacement. The fact that an external monitor works leads me to believe that there is something wrong with the LCD screen itself, not the power/data cables that run it, nor the back-light. To replace the LCD would be as expensive (if not more) as getting a small external monitor and using it as such. just my opinion.

house70

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Apr 21, 2010
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Sounds like you already put more into troubleshooting than most of us here would have. Kudos.
At this point I am not sure if it is cost-effective to replace more parts to it vs. using it with an external monitor, as a small desktop replacement. The fact that an external monitor works leads me to believe that there is something wrong with the LCD screen itself, not the power/data cables that run it, nor the back-light. To replace the LCD would be as expensive (if not more) as getting a small external monitor and using it as such. just my opinion.
 
Solution

natarshia

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Jan 3, 2012
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thanks for the replies. The cost of the LCD is probably 50% or more of getting the same older model laptop replaced. I would get a new LCD if I knew the LCD would work, but I don't know that it would. I have a new backlight, new inverter, and new LCD cable, all three parts are hooked up together minus the LCD screen. I was expecting the backlight to turn on at least. Shouldn't the backlight turn on even if it is not installed in the LCD? So I'm thinking if we got a new LCD and plugged it into the inverter, the same problem would exist. One thing was that the screen didn't have thing showing on it, not even faint. That would lead me to believe that no input was making it to the screen from the motherboard. I thought it was the fact that the laptop thought it was 'closed', but it uses a magnet and I put another magnet on the base and removed it hoping it would reset - still no luck. Any thoughts?
 

house70

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This is the way we learn... trial and error (or success). If you are determined to get to the bottom of this, I would say you could team up with someone from a laptop servicing firm, if you know such a person. AFAIK, even these places send them to the manufacturer for repairs or even easier, for replacements. I am afraid people like us are part of a dying breed: the tinkerer, and with the advent of integrated technology to a deeper and deeper level our passion was rendered so much more difficult to fulfill. It's not like only a few years ago, when one could get to the bottom of a defective capacitor or transistor and get it replaced. Nowadays tech is living off consumerism and a throw-it-away-get-another-one society.
Sorry, I am out of ideas. Logically, you are correct; from a practical point of view, only the manufacturer could possibly know what they put in there and how. If you could get your hands on the schematics, that would be helpful, but I'm afraid these are usually proprietary and not to be released to the public. Reverse-engineering is useful, but only up to a point; usually it is stopped by some permanent bonding solution (adopted by the manufacturer because of cost-cutting) or a lack of some proprietary tool used for assembly-dissassembly. Good luck with this project and please do share with us any progress you achieve.
 

natarshia

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Jan 3, 2012
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house70 - thanks for the reply and I totally agree. Part of my old school techie mentality is 'anything' should be able to be fixed :) It's killing me to think I may have missed something simple, but I guess I did put a ton of effort into trying to fix it - why - because it's someone at my kid's school and i know they don't have a bunch of money to go out and buy a new computer. Thanks for being so much of a responding ear. I wish I did have time and money to figure it out, but at that point I could afford to replace the computer. The parts cost me about $40, the screen might be $200, but I can find the same model for about $300 on ebay. I considered the $40 as learning money.
Happy New Year!!