need help with aftermarket head unit

i have an aftermarker headunit by JVC it was working fine but now when i turn it on the top line of the display does not work and the raido does not work either. the only things that work are the in- dash cd and the changer but no display. i took the head unit out and cheaked all the connections but still nothing. any suggestions???

You nered to contact JVC. Sounds like the problem is located internally on the radio.

The stock Delco unit is pretty powerful for most folks.