WARNING: When the Factory Reset procedure is performed ALL user-stored data (Registrations, User Styles, Multipads, User Voices, User Songs, and MIDI settings) will be DELETED. If the current settings are not expendable, create a backup before executing the Factory Reset.
1) Make sure that the power is OFF.
Reference: PSR420 Owner's Manual, p. 81
2) While holding the [+] and [-] buttons, turn power ON.
3) When the top of the screen reads ''Clr: Backup'' release the [+] and [-] buttons.