One thing to check is the cable, once in a blue moon they get disconnected inside the housing. To do this, remove the 11 phillips head screws from the bottom of the housing, remove the top housing half, and then check the cable connection. Usually this is the culprit when it is completely dead without even lighting up.
If that doesn't fix it, email me at
technicalsupport@deckkeyboards.com and I will work with you to make it right.