Cassette/radio/7 disc cd changer Stero repair issue?

I took apart my magnavox fw36 to fix the CD player and I noticed a small thin washer has fallen off. Now the stereo will not work at all. I plug the power plug in and nothing shows up. No lights. However, wen i press the cassette play button I hear the motor going. Wen I press the radio and cd button, nothing happends. I noticed the cassette belts were worn out so I changed them aswell. Kan someone please help me figure out how to fix the stereo?