Laptop screen help?

[Linkavitch]

So, the screen on my Dad's laptop recently stopped working. It still has a very faint image, but it's hard to see unless it's in bright light. He just replaced the screen so he knows that's not it. The next thing we think is the backlight mighta gone out, but if it was contained within the screen, which we just replaced, that's not it, and if it's not, then we can't find it. Any clues?

EDIT: also, it's kind of an older model (not pre 2000s.) if that helps.

[Don Julio Anejo]

Most likely the backlight. Don't let the fact that you just replaced it fool you - there's a bad egg in every basket. You probably just got a faulty component.

[valadil]

It's definitely the backlight. The replacement screen must have had a bad one.

[Jimorian]

If the original screen and the replacement both have this problem, my guess is that it's the connection in the laptop body that powers the backlight, or that particular lead in the ribbon cable is bad (if it wasn't replaced during the swap).

[KuReshtin]

Most laptops have an 'inverter card' that powers the backlight on the screen.
or rather, it converts the power from the system to be enough to power the backlight.

If that's gone, you need to replace that to get the backlight going again.

Backlight problems are usually pretty tricky to diagnose as it could be one of four different components that are faulty.

Either it's the inverter card, the LCD screen, the LCD cable (that goes from the system board to the screen) or the system board itself.

If it's the inverter card, it should be pretty easy to replace, as it's usually located just under the LCD bezel (the frame part that goes around the LCD screen).