How-to: Lenovo Laptop Dim LED Screen Backlight Fuse Repair
Screenshot of Lenovo Motherboard
How to identify the cause of your dead laptop screen
If you have a Lenovo laptop with a Dim Backlight, and the desktop is faint but visible this usually means that the main components of the motherboard are working fine. If you look in the photo above you can see the arrow pointing at the fuse on a lenovo laptop motherboard
However there could be a bad fuse, and in order to determine which part to troubleshoot you need to determine if you have one of two types of LCD Screens for laptops CCFL, and LED style screen, if you have the LED style screen the cause is most likely a blown fuse on the motherboard. In most cases newer laptops, are using a LED style back-light instead of CCFL‘s, which negates the need of an Inverter, so now manufacturers are placing a fuse on the motherboard, to protect the screen from surges. However sometimes a momentary problem can blow this fuse, and kill power to the screen rendering the computer unusable. however with a little time, and a lot of heat (soldering) you can replace this puppy. Identifying the proper fuse and replacing it will safe you hundreds in repair costs. when you don't want to attempt this computer repair yourself, you may be able to find a local shop that will do this type of soldering, which is still cheaper than a replacement motherboard.
If you have the CCFL Style screen (the short definition is that it is a compact fluorescent bulb). In this case it could be a bad inverter. The inverter is comparable to the ballast in your everyday shop lights, it ramps up the voltage in your laptop high enough in order to allow it to fluoresce and provide light behind the screen.
Leave me a comment if you have any questions, I have identified numerous fuses on various laptops. If your model isn't addressed here, leave a link to a High-Res photo of your board, and I'll see what I can help you find.