How do you enter code on stereo for a pulsar 2001?

There are six numbers on stereo panel 1 2 3 4 5 6. to enter code only need first 4 number buttons. ( 1 2 3 4 normally used to change ch. ) if your code is eg 6745 first press 6 times using nimber 1 button 7 times using number 2 button 4 times for number 3 and 5 times for number 4. that's all. if your pannel says err you have to wait 1 hour yes 1 hour till the pannel display "code"