Yamaha Disklavier Silent Mark III Service Manual page 22

DU1A
20. Switch Box Unit
(Time required: About 1 minute)
20-1 Remove the four (4) screws marked [071S]. The switch
box unit can then be removed. (Fig.12)
Front view
21. HP (1/2) Circuit Board
21-1 Remove the switch box unit. (See procedure B-20.)
21-2 Remove the VOLUME and REVERB knobs, and remove
the two (2) hexagonal nuts marked [21GB]. The HP (1/2)
circuit board can then be removed. (Photo.16)
22. HP (2/2) Circuit Board
22-1 Remove the switch box unit. (See procedure B-20.)
22-2 Remove the two (2) hexagonal nuts marked [H]. The HP
(2/2) circuit board can then be removed. (Photo.16)
23. CTRL IN U Circuit Board
23-1 Remove the switch box unit. (See procedure B-20.)
23-2 Remove the hexagonal nut marked [I]. The CTRL IN U
circuit board can then be removed. (Photo.16)
22
[071S]: Truss Head Tapping Screw-1 4.0X12 MFZN2BL (03747270)
(Time required: About 5 minutes)
(Time required: About 4 minutes)
(Time required: About 4 minutes)
Front view
[071S]x4
Switch box unit
Bottom view
Switch box unit
(Fig.12)
CTRL IN U
[I]
Switch box unit VOLUME knob
[21GB]:Hexagonal Nut 12.0X14X2 MFZN2BL (VB508600)
[071S]
HP (1/2) [H] HP
[21GB] REVERB knob
(Photo.16)
(2/2)