Help coby ktros 9742 lcd probs


when i turn on the lcd dispaly is so faint/dark that i cant even see the coby or android boot logos inless in direct sun i took the lcd out because i thought it might be the back light.Tride it in another tablet and it worked fine.
and tride the onother 1 in the coby and no diference still dark.
so i was wounder if it was a power isu.or firmware problem
i have the same problem too.. did anyone have solution for this problem.. or anyone have schematic diagram for coby kyros mid 9742? thanks in advance.. :)