raysh22a4

whats up guys, i have a problem with my D2 i want to use my stereobutcant every time i power it up all it shows is the disk error, but i can hear the radio but i cant use the screen. now do i have to have a working nav rom to use my d2? i tried buring the nav rom on 3 types of dvd dl and i have no luck.. i want to try to fix it before i send it in to pioneer.