Screen Broke... Couple quick q's

Hey there,

A few days back my LCD screen on my computer randomly faded to an array of horizontal bars without a noise or indication. I went to reboot, and the screen pulled up the BIOS and OS like normal. Eventually, again, all of the bars came back up. So, I booted up into windows to see if it did the same thing, sure enough, not the driver. Hooked it up to external screen, worked fine, not the video card (motherboard). SO, I took it apart, checked all connections, a few obvious solder points, nothing that was out of the norm, put it back together, no dice.

Now I'm left with two options, replace LCD and inverter board together, or just inverter board. I haven't dealt with a failure of a LCD screen before, so I'm wondering what the symptoms of displaying for a few seconds-minutes and then failing to a garbled screen would point to. I'd love to be able to only replace the inverter board for obvious reasons, but need some advice.

Thanks much.

 

Have you checked the ribbon cable on the back of the lcd?
Usually the cable which connects the lcd to the motherboard becomes loose from the continual opening/closing of the lid.
If you can, take the lid apart and remove the ribbon cable on the back of the LCD.
Use a q-tip and some rubbing alcohol to clean the connection ends of the ribbon cable and the port on the back of the screen. Make sure the connectors are dry before reconnecting.
Than when the connectors are dry, make sure that the cable is connected properly. Than use a piece of tape to secure teh ribbon cable to the back of the LCD, so that the cable cannot become loose again.
Than hopefully that fixes your problem.

Another thing you should look at is the inverter. The two main problems which occur with lcd's are either the ribbon cable coming loose or the inverter burning out.
You can check the voltage coming out of the inverter with a voltmeter. The voltage output is generally between 14 and 20Volts. If the inverter measures like 5 volts when the screen is showing nothing, than the inverter is most likely the problem.

K-TRON

 

"LCD screen on my computer randomly faded to an array of horizontal bars..."

It looks to me that the problem is related to the LCD cable or the LCD itself. If there was a problem in the inverter, you should either see a dim screen or a complete black-out (due to the non-functional backlight). I have never seen an inverter problem causing horizontal/vertical bars in the LCD...

 

Awesome,

Thanks for the tip on the inverter, I didn't think that that could cause the bars. I'll clean everything with some rubbing alcohol tonight, but I've ripped her apart and reconnected everything and checked it all and I know it wasn't just "loose".

I'm really hesitant to replace the screen even if the cleaning doesn't solve it though, because it does display a perfectly correct image for a little while before going to the "bars". I was hoping I could fin a loose solder joint that was obviously repairable or something of that nature, so ANY other suggestions are more than welcome, as I have much more time than I do many.

Thanks