nano display is black

Hello there, rlerma.

The following Knowledge Base article provides some great troubleshooting recommendations:

iPod nano (6th generation): Hardware troubleshooting

http://support.apple.com/kb/TS3474

Particularly:

Screen is unresponsive and displays Apple logo

• Reset iPod by holding down the Sleep/Wake button and Volume Down button until you see the Apple logo appear. If the Apple logo appears on the display, connect iPod to a computer and verify that it appears in iTunes.
• If the Apple logo does not appear, or if the iPod is not seen in iTunes, try putting the iPod into disk mode and restoring:
  • Reset the device (press the Sleep and Volume Down buttons simultaneously until the display turns black—about eight seconds).
  • When the display turns black, hold down the Volume Down and Volume Up buttons simultaneously until the device enters Disk mode.
• While the device is in disk mode, connect it to iTunes and try to restore.

Thanks for reaching out to Apple Support Communities.

Cheers,

Pedro.