stuck in protect mode?

hi there,please help i have a sharp cd-ba1700h (no remote) and i attached the speekers to it then turned it on it worked fine for 2 sec and jumed on to 'protect' mode now i cant get this mode to deactivate i've tryed turning it on and off a few times (its has not been banged, or nocked, or droped in any way) but nothing works even tryed what the manule says to resett the microcomputer and that worked for a few min but then when i went to use it, it went back to protect mode, whats happend does this mean i need the remote or is it broken should i just bin it its a great hifi can it be saved?thank you for your time i realy hope you can help.thank you