stereo safe mode

hi
sorry this aint a subaru question but does anybody know how to switch of safe mode on a philips stereo in a 99 astra?girlfreinds dad got a new battery and stereo hasn't worked since
he has the unlock codes which he paid for from opel the last time it happened an opel mechanic did it then and only took two minutes.i try do it few times and nothing happens.
any advice welcomed

thanks
billy

Try this

activating the code

Press and hold the AS button and switch the set on. The display will show 'CODE' followed by . Enter the code using presets 1-4 and again press the AS button. The set will now operate.

code entry

Upon switch on the display will show 'code entry' followed by the number of attempts left and . Enter the code using station presets 1-4 and press the AS button. The set will now operate

deactivating the code

Press and hold the AS button and switch the set on. The display will show 'CODE' followed by the number of attempts left and . Enter the code as above and the set will operate

thanks will try that