Radio Code issu
 

Hi there, trying to solve a radio code problem in a 2001 Mitsubishi Galant. I have a code in the owners manual however I can't put it in the radio using numbers 1-4. Apparently I need to push number '1' eight times in order to get number '7' ...etc - is this correct? When I push number '1' more than three times, the radio goes into the '5 minute mode' where it works for 5 minutes and then switches off again displaying 'CODE 1'. This makes it impossible to enter the first number of the code.... I have tried holding the 'ON' and 'EJECT' button at the same time but that displays a blank screen.

Car was bought brand new 10 years ago.