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Laptop Screen Backlight Fuse (Dell Inspiron 7559): is this the right one?

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I'm trying to find a broken fuse for a Dell Inspiron 7559 laptop.

I'm not sure if I've located it or if it's a fuse for something else. How can I tell?

Here's a picture of what I found. (it's the "F" fuse next to FS1)



Active Member
FS1 is possibly a "Polyswitch" style solid state fuse, a PTC resistor. They have that case style with the notched ends.
Does it read as a low value when you test it with a multimeter? It should be low ohms (single digits) or fractions of an ohm.
That style is normally self-resetting, they go back to normal when the overload is removed.

Some laptops do have a conventional miniature wire fuse in the power input circuit. The ones I've seen in that application look like a miniature axial resistor.

Some examples of miniature fuse styles:

Edit - just searched the computer model and found it has an option for a backlit keyboard.
The legend near the connector in your photo implies that's what those components are for.

If the problem is the screen backlight, you need to look near where the screen connections are on the main board.

- Found another post re. the backlight problem, apparently one cause is a failure of a mosfet, Q7.

See the "Best solution" post in this thread; it also has a link to a schematic.
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