I JUST INSTALL A AVIC N4 WHEN IS START UP IT SAID , PLEASE INSERT THE APPROPRIATE DISC. THE DISPLAY IS BLACK AND NO OTHER FUNCTION WORK . AFTER PUTTING IN A BRAND NEW EAST COAST RED N4 DVD IT STATE ( ATTENTION THIS IS NOT THE APPROPRIATE DISC, PLEASE INSERT THE APPROPRIATE DISC) IT SAID THE SAME THING WILL WEST COAST DISC

 

please help