Basic troubleshoot for a cd changer?

[peace brainerd]

I hope this is not an inappropriate type of post for this forum.

I've got a Yamaha five disc changer in the basement workroom. Got it second hand a few years ago, label says it's from 1983. It's in A1 physical condition. Which is kind of a shame now.

Worked wonderfully perfect until yesterday. New disc rotates into position, display just reads zeros, wont start. Push play, nothing. Ten seconds later the display reads "OPEN" and the tray extends.

Opened the case. Looks factory fresh. When I hit play the the eye and disc drive shuttle comes up and clamps the disc but just sits there. Two seconds later it spins for about five seconds and stops. All the while the display reads zeros. When the disc stops spinning the display says "OPEN" and the tray extends.

I very gently cleaned the lens, blew out all components, looked for anything loose, unplugged and replugged all removable connectors on the boards in case any pins were oxidized.

It's just not worth getting professionally repaired and my diagnostic skills don't really go much beyond checking discrete components like diodes and resistors.

Any other little "check firsts" that you'd recommend before It goes out to the sidewalk?

Thanks so much.