kenwood kdc-241 in protect mode

[jonnybigballs]

hi, i have a kenwood kdc-241 for repair, it fires up and just says protect on the screen. i have removed the audio output ic but it is still saying the same message, im thinking it could be something related to the proccesor but i dont have a circuit diagram and have run out of ideas now!! if anyone can help, please let me know!!! many thanks.