Replaced broken lcd with new one and getting rubbish on screen of new one... help?

thekooman

hi all,
just replaced a screen in a HP 550 laptop for a friend. the screen is showing gibberish, flickering with reds.
i plugged it into a plasma with a VGA and it shows fine. I rechecked all the connections but still its the same.
any ideas anyone?

what was the old screen symptoms?
Did you replace the inverter?
Checedk the LCD cable connection running up the back of the screen?

thekooman

the original LCD was punctured/cracked; ear buds were left in between the keyboard and screen and closed!
i didn't replace the LCD cable or the display inverter.
as i said i rechecked all the cable connections.

I think the LCD is ok. I might have to get an inverter first to see what the problem is and then a display cable if its not that. there is only 3 parts to it so have to deduct from that.

edit: i have contacted the seller of the screen... got it on ebay. id say the screen is a dud. didn't realise it was a used item when i bought it. the backlight is working in it so its hardly the inverter and anyways before replacing, part of the screen was still showing so in other words the cable and inverter were ok.

From what you are describing, id be inclined to think dud myself. Possibly someones attempt to resolder a ccfl bulb gone wrong.

Only other advice i could give just to 100% confirm would be to use a multimeter to check the frequency outputs of the inverter, but as you said doesn't seem to be the problem. And cable failure is simply cable failure, hardest thing to diagnose!

Owen

Inverter wouldn't cause tthat. It's going to be either the screen, or the LCD cable unfortunately. Cheaper of the two options to investiagte would be the cable.

thekooman

many thanks for the replies all.
had an idea there; ill connect up the old screen again. if i can partially see the screen (because it was cracked) then its not the cable or the inverter (don't think it is that anyways).
i contacted the seller and they said it was tested before sending! :rolleyes: they'll take it back anyways.

thekooman

checked the old screen and i can still see the BIOS text on startup and the like so its not the cable or the inverter... back it goes! thanks for the help all.