How can you fix the Radio onoff button to stay in ie power radio off?

Depends on radio type. Most of these switches are 'momentary contact, which is to say the switch makes contact, then returns to its original state, sending a pulse. If your switch is of this type, the mechanical function sounds fine and the prob. may be a logic circuit and not the switch. The on\off switch on my radio is also combined with the volume knob,(pushing vol. knob turns unit on\off.) I'm afraid these are probably un-fixable. Sorry for being so verbose.

I HAD THE SAME PROBLEM ON 95 LINCOLN AND WAS QUOTED 300 DOLLARS TO REMOVE FIX AND INSTALL. AFTER MANY TRIALS I FINALLY CAME UP WITH AN EXTERNAL FIX FOR 5 DOLLARS. WILL SEND PART AND INSTRUCTIONS UPON RECEIPT OF CHECK OR MONEY ORDER TO RADIO 45328 LORIMER LANCASTER CA. 93534.