That happened to my old m11x, it happened to be a cable that's with the keyboard, I changed the whole keyboard and it worked but other lights kept working... Im not sure how's the wiring on your laptop but if they worked before you took it off and weren't working after you had it opened mostly a cable or connection are unplugged.
I recently bought an Alienware 18 notebook from a coleague and the first thing I done was format and install a new Windows 7. After, upgraded to Windows 10. The former owner told me that the lights wasn't working well... indeed, they used to work on thier own. So, trying to fix it, I executed many solutions found in foruns and none worked. But, during a try, when I disassembled the notebook to see if there was some wire disconnected (apparently not) I assembled everything and, for my surprise, the lights never came on again. I tried everything again, even clear the BIOS (that I failed), and nothing again. Disassembled to check if I left something unplugged, but everything seemed ok.
All the lights are off: the power button (the button works), status lights, cover lights, logo light and sided lights.
In the first moment, I didn't noticed, but today I noticed, during the unninstalation of the Command Center, that in registry, the 2 records says Model: Unsuported:
Also, in system tray:
And the AlienFX Tester:
Can someone help?
I'm using Windows 10.