Carousel won't advance, fwd, back and remote doesn't work, just makes a faint buzzing sound, as does the timer. Select button sounds right but doesn't catch the slide.

If the select button functions correctly, then it sounds like you have a wire broken or a wire nut that holds a bundle of wires together has fallen off. If it was the solenoid link, then the Select function would not work. After removing the bottom cover, look for the orange wires, That is the cycle circuit. Look for a broken or unattached orange wire from the side button and the remote receptacle.
The other possibility is that the direction lever is stuck, bound up or the direction lever spring is broken. The attached image of the top plate of the slide change mechanism will show you the end of the direction lever. It should move freely, up & down on its center pivot. You should see a small, wire spring, about 2-3 inches long on the lever. If the spring is not there, or the lever does not move freely, that may be the cause of no forward or reverse.

Have you checked the diode could be feeding back through and limit current.

Your problem is most likely related to cycle contact adjustment. See the attached illustration for the parts involved and the SPECIFIC POSITION of the contact parts:

your pressure sensor is not detecting the water level change

Your projector most likely has a broken Link, which connects the cycle solenoid plunger to the cycle lever. The buzzing you hear is the cycle plunger in the cycle solenoid. This is a quite difficult repair for a trained tech. Parts are available at: www.micro-tools.com I suggest you contact an authortzed repair dealer to make the repairs.

door lock is the first place I would start. If it keeps doing it after the lock checks good, then it would have to be the control board.

Chances are, with a projector that old, that you have a broken "link". The "link" connects the cycle solenoid to the slide change mechanism. The "link" is made of plastic, and it gets brittle & cracks over time. The buzzing sound you are hearing is the solenoid plunger bottoming out in the solenoid coil. This is a difficult, but there should still be parts available. I suggest you contact a factory-trained repair dealer to get your projector back working for another 20 years.

The purpose of the "SELECT BAR" on a Carousel 650H is to eject the slide. If you press & hold the select bar it allows you to rotate the tray to the slide you want (or Zero & remove the tray). If you can not advance or reverse the slide tray using either the remote buttons or the buttons on the side of the projector, then chances are you have a broken part in the slide change mechanism. The possibilities are numerous, and really requires a trained tech to analyze your specific failure. Sorry the news isn't better (or simpler!).

By your description, chances are you have a broken solenoid "link". This "link" connects the cycle solenoid to the slide change mechanism. Over time these plastic "links" get brittle and crack. This is not an easy repair, but there are still parts available. Contact a factory-trained repair dealer to get this repaired correctly, and it should run another 20 years!!

Depending on your interpretation of the 'buzzing' sound compared to mine, I'd say it may be a relay chattering or the motor trying to start up but the windings are beginning to fail. You may want to clean the motor housing from dust etc and make sure that you do that with the power disconnected. Also: with no clothes in teh dryer..try rotating it around and feel for any spots in that rotation that may be binding.. if the drum has excessive restriction while rotating.. the motor may not have enough torque to overcome that and just buzz,,, Hope that helps...