How can i fix my Grundig car 200 radio?

Hi- i have an N reg car with a Grundig 200 radio which just displays the word "SAFE" I have tried pushing the as button and putting in the code but it just returns to safe mode. Has anyone any ideas driving without music is driving me Mad. I think it may be conected to a time when my car broke down and the alarm went off the mechanic did something under the bonnet to stop the alarm and the radio has been in safe mode ever since