Oct 222011
 

If you have a lenovo laptop with a Dim Backlight, and a LED Screen, the cause is most likely a blown fuse on the motherboard.  In most cases newer laptops, are using an LED’s instead of CCFL‘s, which negates the need of an Invertor, 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.  Jump over to this post to get the link for the FUSE you need.

SMD FUSE Sources

 

May 302011
 

If you are looking to brighten or dim the led/lcd screen on your laptop, most dell’s, well any laptop, will have a circle with ridges in blue either on their left and right arrow keys. In order to change the brightness up or down, you hold down the key, then the

Dell Image Brighten lcd screen

Dim Dell Lcd Screen

appropriate function key with the gear symbol in order to adjust the setting

 Posted by at 7:22 am
May 252011
 

________UPDATE September 2016___________

Update – I’ve moved this post from the old location at nwapchelp.wordpress.com
For those looking for assistance on finding the fuse on Various models, Please provide photos near the LCD Connecter, but also near where the power charger plugs in. I am seeing the possibility that some fuses may be located over near that area.
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This applies to Dell, Sony and many other manufacturers of laptops with LED based screens.

These issues are also commonly search on as no backlight.  In most cases when you know the screen is good, it will be a power issue from the motherboard causing the backlight to fail to power up.

On the motherboard you should find a fuse labeled f1 in the case of dells, that is approximately .8 mm in depth, and 1.55 to 1.6mm in length. This fuse protects the voltage circuit to the led’s. in the case of a dell inspiron 1545, it is a 3 amp, 32v fuse, that can be replaced relatively cheaply. Make sure tho that you have isolated the cause of the fuse blowing. Good luck!

The Fuse is located on the Dell Inspiron‘s just below where the led video cable connects to the motherboard.
Use a Continuity Tester or Multimeter to confirm whether or not it has blown.  If you find any other fuses or different locations, feel free to comment, or even link to pictures of other fuse locations and I’ll approve them.

For other manufacturer’s the location is not so obvious unfortunately.

Sony Vaio VGN-TX5XN Possible Fuse locations for either LCD or charging. The two that are circled need to be tested for continuity.

sony motherboard fuse locations

SONY vaio No Backlight PCG-6121M

SONY vaio No Backlight PCG-6121M

ASus K53

Dell XPS 1701 with blown mosfet?

looks to have a blown component but its not a fuse.

 

 

If you post a comment with photo’s, take the time to make sure that when zoomed in the component labels are still legible. The components that have to be viewed need to be as sharp as possible, with as little glare as possible.

1 tip is to balance the phone on a stack of books or something to help steady it, and take the photos in smaller sections, overlap them just enough that I can make out where one stops and another begins.