Seeking Help - Unusual Issue on old Kodak Carousel Projector

Hello all,

Brand new member, apologies if I'm posting in the wrong place, but this seemed the closest fit.

I've got an old Kodak 550 carousel slide projector I just took out of storage after many years. It seems to work fine, except the reverse function does not work.

Specifically, forward works just fine, but whenever I press reverse, something makes a very short buzzing sound (like a second or less), the carousel advances instead of reversing, and - strangely - the lamp turns off. It appears the lamp/fan operational button ("low" or "high") comes up very slightly when this happens, and re-pressing it turns the lamp right back on. The projector can still be operated fine otherwise, both before and after this glitch with the Reverse button.

From searching online I am very familiar with the solenoid problem, but the solenoid seems to work fine for the Forward function here, and even with Reverse the solenoid doesn't seem dead - it sounds like it's being triggered.

I'm wondering if it's something to do with a mechanical transport related part - but in general, all the online forum answers seem to indicate that if it's one of the transport pieces it should affect both forward and reverse.

Any ideas? Am I missing something totally obvious? Thank you very much for any hints or suggestions!

Have you examined the controller to make sure the switch contacts are clean and that there's no short-circuiting between functions?

First thing I'd do is check the switches for dirt and corrosion.