Yamaha 415 (D65) Attack, Wah Brass, and Rhythmic Chord

[Orangeflipflop]

I've recently acquired a Yamaha D65 (415 Where I'm from, but as far as I know it's the same organ.) and it has a few faults. The attack stops don't sound at all, and the Wah brass doesn't either. I can hear a faint sound difference with the volume all the way up when I turn on the Wah brass. The Rhythmic chord features are almost silent, but they were working fine a few days ago, and the sustain slider seems to have stopped affecting them. The last thing is the "Sound 3" on the arpeggio section is stuck on and is quite loud in comparison to the other two sounds.

The tabs up top would be cleaned by D5, correct?

[Orangeflipflop]

Just realized, the 415 is the D85, mine is a 405.