all you have to do is enter the code when the radio starts up and the display goes blank it is in 10 digit display mode
you must have the 8 digit ver
so after the unit is working with a blank display do this
turn the unit off
then press and hold 3 and 5 and while held turn the unit on keeping them pressed untill the unit bleeps it will then work
some models the no's are 3 and 6 try this if 3 and 5 fails
regards
les evans
April 2006