Hello acerocks!
most coded stereos follow the same sort of code imput,try this
1.switch on,code symbol appears,press pre set button 1
2.press one of the tuning buttons < > to enter 1st digit of code.
3.press pre set button 1 to store 1st digit
4. follow steps 2-3 to enter rest of code
5.when all 4 digits have been stored you should hear a two tone beep to let you know the code has been entered correctly.
hope this helps!!!!