Kurzweil PC88 - Page 87

Chapter 4
Troubleshooting
LCD wavers, cannot change sound
1.
5.
6.
Try selecting another sound in the Sound/Setup
Select section. If the unit plays another sound but
skips quickly back to the Classical Piano sound,
chances are a control panel button is stuck. In this
instance, you may also see two LEDs that are not
normally lit, lit at that same time; i.e., Classical
Piano and Stage Piano.
Remove the Control Panel Board. Check the
switches and caps. Check solder connections.
Reinstall board and check for proper operation.
Refer to Schematic Diagrams. Check for correct
voltages in signal path.
Find and replace bad component(s).
If necessary, order circuit board replacement.
LCD dim/not lit: Characters are present and LEDs are lit
1.
Check LCD contrast adjustment located on the rear
panel. Turn the pot back and forth to see if there is
any change.
Check LCD backlite cable at J15 and LCD ribbon
cable at J7 on the Engine Board.
Check backlite solder connections on the LCD
Board.
Check solder connections on the Engine Board.
Refer to Schematic Diagrams. Check for correct
voltages in signal path.
Find and replace bad component(s).
If necessary, order circuit board replacement.
PC88 Service Manual
4-7