Power pack over heated

Some Yamahas have a current limiting polyswitch, but if you have tested the unit with a different power supply and it still doesn't work, there is a good chance yours doesn't or it did not help. There is a good chance that your power supply is a switch mode type so once it failed it best to buy a new one, but before you plug it into the keyboard you will want someone to test it to make sure the voltage conditioning section of the dc in pcb is not shorted. If it is, best to replace the pcb or get a. Per job repair.