I have a 04 Excursion with the 6 disc CD player. I removed the head unit to "bench test" another 6 disc player. When reinstalled my original unit, I get an "DVD/CD Error" message on the LED readout. The radio works fine. I have removed and verified the plugs are tight, I have disconnected the battery for a period of time, the fuses, etc... The unit will not play the CD's, won't eject the installed CD's etc... Any help would be appreciated. The unit worked perfectly before I removed to test another head unit. I have not checked the DVD player if functioning as before.