LCD's are not rocket science. On these there are few things that usually go bad, either with wear or accidental damage.
1. Inverter - if our LCD is backlit with CCFL's (not led), this usually goes bad over time. Your monitor won't light up, but if you flash a light you will see that there's an image, just not backlit. Typically you can just buy the inverter and replace it.
2. AD board - Most of the time the caps go and and you have to re-cap the ad board. Fixes most problems when there's absolutely no image, but there is power to the lcd.
3. Power supply - no power at all, it is easy to test to see if the power supply is putting out voltage, also you can check the caps to see if they are bulging.
The other issue is LCD panel itself, at that point, you are better off buying another monitor. On laptops it is easy to find a replacement lcd panel, but for these monitors, no so much.