Kurzweil KP100 LCD Black Bar

[Skystrider17]

Lightning got through the surge protector during a storm and now when I turn on my Kurzweil KP100 there is no sound, and LCD shows black bars (see picture). No visible signs in circuits, all capacitors appear good; tested to confirm. Best guess based on googling is it's a bridge rectifier, or some other voltage metering component (not an EE; but know enough to be dangerous). Would greatly appreciate any help; just a hobbyist but love playing.

 

[ioannes]

Lightning got through the surge protector during a storm and now when I turn on my Kurzweil KP100 there is no sound, and LCD shows black bars (see picture). No visible signs in circuits, all capacitors appear good; tested to confirm. Best guess based on googling is it's a bridge rectifier, or some other voltage metering component (not an EE; but know enough to be dangerous). Would greatly appreciate any help; just a hobbyist but love playing.


View attachment 2892

Black squares are typical of a not-initialized LCD; I may think the main microcontroller of the keyboard is no longer running the firmware.
Do you see any LCD data update when you turn-on the power or do you just see the backlight on and nothing changes on the display ?

 

[Skystrider17]

There's no LCD data update or text. Usually if I press the power button briefly the LCD screen will flash on briefly with no characters, and then turn off. When I hold the power button for a little longer it will turn on and show the black bars (as pictured). No buttons or keys register any change; have to unplug in order to turn it off.

 

[ioannes]

There's no LCD data update or text. Usually if I press the power button briefly the LCD screen will flash on briefly with no characters, and then turn off. When I hold the power button for a little longer it will turn on and show the black bars (as pictured). No buttons or keys register any change; have to unplug in order to turn it off.

I am sorry, what you wrote hints my thought: the microcontroller is not working. If you look at the electronic board you should find some burnt track or, worst case, some burnt chip.