Alienware m15x Manufacturing Mode: Level [FN]

Hi there,

I'm using an old model of the alienware area 51 m15x series and since today I got this weird message when I'm booting the device. After a very short loading screen a message appears which tells me:

Manufacturing Mode: Level [FN]

Press FN x to return, blah blah...

So I've searched for a solution but I didn't find any which fits on this problem. Entering the bios was possible so I restored the default settings. This didn't affected the upcoming of this message. I checked for my bios version it is: vX36 P3A37.

I also can boot into windows, but since I got this message my keyboard does not react properly. It needs two to three presses on any of the key that the system recognize it.

So if any of you guys have an idea how to solve this, i would be very thankfully! 

Note: Please excuse my bad english, i didn't found any help in german language...