Yes, that is fine. We can do the repair on your own time.
Unplug the keyboard, and hold the REC button for one full minute to drain all of the power from the keyboard. While still holding REC, plug the keyboard and turn it on. It will initialize. Please let me know if it does not.
If it initialized and still doesn't work:
What I will need you to do is open the keyboard, and identify the parts as follows:
Amplifier-Has the big capacitors, and is connected to the output jacks.
Headphone amplifier-Connected to the headphone jack.
Motherboard-Nothing on it will make sense. It's the brain of the operation, and is not where the problem is.
Pitch bender-Feeds into the mixer.
Tone generator-Also feeds into the mixer.
Mixer-Feeds into the amplifiers.
I need you to test voltage at the input of the mixer from the tone generator. Test for .3vdc, or in that range. It will vary depending on how hard you hit the key. When you locate that voltage, test the output of the mixer. Do you have output? If not, we need to replace the mixer.
Let me know if you have any questions along the way. An initialization may fix the entire thing, so first concentrate on that. Open the keyboard as a last resort.