It seems to have a power connection, but not a data connection. The 30-pin dock connector has separate "pins" for power and data; the ones for data may not be connecting properly. To rule out a faulty USB docking cable, try a different cable if possible (the newest one you have).
You can also try shutting down (powering off) the MacBook. If you have other USB devices connected, disconnect them all. Do this to Reset the iPod
Learn how to reset your iPod - Apple Support
Start up the MacBook, run iTunes, and connect iPod to a direct USB port on MacBook by itself. Again note if iPod's screen indicates a connection (even if the iPod does not appear in iTunes or on the Mac). If that does not help (still no response except for battery charging), try putting the iPod into Disk Mode
Putting iPod into Disk Mode - Apple Support
Then, connect it the same way again. If iTunes picks it up, it may prompt you to do a Restore, with a message about "recovery." If you are OK with erasing the iPod, tell iTunes to proceed.