Help needed! Anyone with extensive knowledge of the LED system? Mine dont work anymore (after hinge replacement from Dell)

If anyone can help me out, I'd be much obliged! Here's the story.

I started having hinge problems in December or so of last year, My warranty was set to expire in January, so I promptly got Dell to replace the hinges. As you guys know the hinge replacement involves a whole lcd assembly replacement.

In the last few days I've noticed that my LEDs dont work at all (Notice its 6 months later). I only used my m11x sparingly, perhaps 3x a week, and I always resumed it from sleep, and had the led's off anyway (to save battery).

I got to thinking about it, and I don't beleive that the LEDs ever worked since the LCD replacement, so I went ahead and opened the m11x up just to verify that all the cables were securely fastened. There were no loose or frayed cables, nothing that would explain why the LED's didnt work.

Now here's where I need an expert. From what I can tell, the LED board (under the power button above the keyboard) is powered by a cable coming out of the LCD assembly. My theory is that that cable is not connected properly inside the LCD assembly. Is this the correct? Anyone know more about the cabling diagram of the LEDs to know what else could be the problem? The LED's don't come on when the system is first powered on, which indicates to me its not a software problem. Should I bother with replacing the LED board? Is there any way to test/figure this stuff out?

 

The cable that comes from the lcd to the board is just for the "alienware" on the lcd.

The power to the board comes from the flat blueish cables.

Remove the keyboard, check cables there. Remove them, and look for folded over or bent metal pins (on the cable)

 

Yea, the only cables that go into the lid are for display, the antennas, and the alienhead logo on the lid.

I would re-check to make sure the ribbon cables for the keyboard are in properly and all in-tact and making contact.

Also are you saying that you didn't realize for 6 months that your lights didn't work at all? Because if they just died one day 6 months later, i highly doubt it was due to the Dell repair.

 

Yeah, I am saying I hadn't noticed it in about 6 months.

For the first several months I had the laptop, I used it in my living room (dark) to play games with my wife in the room. Once January rolled around, I stopped using it at home, and used it solely for work. I travel for work, and I use it as my work PC now. I only ever boot it from sleep, and I had all the lights disabled.

I honestly believe that the first time I tried to turn on the lights since the repair was a few days ago, when I couldn't get any of the lights to turn on. I'm not saying that the dell repair was definitely the problem, I'm just saying that I don't believe that the lights have worked SINCE the repair, and I hadn't fiddled with it until I noticed it wasn't working.

 

As everyone else has mentioned, it's most likely one of the two cables that connect the keyboard to the motherboard. Follow one of the disassembly videos online and verify that both cables are plugged in correctly. I'm assuming one provides I/O for the keyboard and the other is for powering/I/O of the LEDs.

This is the video I used to disassemble my m11x:
Alienware M11x Teardown **READ SAFETY PRECAUTIONS PRIOR TO REPLACING PARTS** (Official Video) - YouTube

You can see the two cables I'm referring to at the 3:38 mark.

 

Well have you tried rebooting it, lol? Keeping the laptop in a permanent state of hibernation between usage can cause issues, computers actually NEED to be turned off so when they are rebooted they can re-load everything fresh.