the function keys didnt work or the LED's itself? either way, bad led, or soldering weakened on the switch that made it non functional, or just a switch gone bad, all you need for the first two is removing the solder and soldering it again or if switch is bad desolder switches, pop in new ones and solder them again, after all this is Deck not TG3 with metal back plate where in order to fix 1 you need to desolder all, ouch!