Thanks for getting back to me. You were offline when I responded earlier.
Do you know the voltage and polarity of the incorrect power lead that was fitted?
Ok, depending on what incorrect lead was used, it may have caused irreparable damage to the internal circuitry of the keyboard. This is because the keyboard is designed for use with a particular voltage and polarity power supply adapter.
Incorrect voltage or polarity will damage the sensitive internal electronic components.
Since the keyboard is not functioning with the correct power lead or with batteries, it seems that damage has been caused and it will require a repair.
You can take it to your local Yamaha music dealer, or contact Yamaha directly to arrange a repair:
Let me know if you need any further information.
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