No more keyboard backlight - Vostro 3550

I don't know what's happened but since opening my laptop to do some repairs, the keyboard doesn't light up anymore.

In Quickset, the BacklitKB.exe says 'Unable to detect the backlight keyboard'.

Fn + F6 doesn't turn it on.

Fn + right arrow doesn't turn it on.

There's two ribbons on the back of the keyboard. A wide one that controls the keyboard and a thin one that controls the backlight, to my knowledge. The thin one is currently connected.



Although when I unclipped the keyboard from the chassis, the clip on the motherboard holding the ribbon isn't as firm as it should be it. It doesn't really click, it's a little loose. It will hold the ribbon in place but it's very easy for the ribbon to come out without pulling the clip up. Not sure if that's the problem, or if it's the ribbon or the keyboard broken. Or a software issue.

I can buy a new keyboard for £20, but before that, wonder if anyone can throw any light on the matter. Thanks.

 

Your connections look good on the clips however I would advise for you to try to put some clear tape to make it more secure. When applying the tape apply pressure towards the direction of where the clip goes in. We've had a couple of these Dell laptops where the connections were loose and by doing this made the keyboard work.

 

Thanks metzen. I just put some sellotape on it in the direction of the clip but still nothing. Even pushing firmly down with my finger and opening BacklitKB.exe, it still says 'Unable to detect the backlight keyboard'. Seems to be broken hardware. I ordered a new backlit keyboard from ebay. If that doesn't work, then it must be the motherboard connector.

 

The ribbon cable for the backlight is probably damaged. Most of the times the damage occurs on the exposed pins or in portions where the ribbon cable bends. With a good light source and a magnifying glass, you may be able to spot the damage. Unfortunately you can't just replace this cable without a new keyboard.