Orginal Head Unit Not Working , Code Sign Dosent Even Show Up

[Djlosty]

hi , i have just put my orginal hu back in and it dosent seem to be working , it dosent even come up with the code , or digits to input , ive tried putting code in but nadda , all it does is bleep if u hold a button long enough , does anybody no how to solve this??


THNX

George/Losty