nintendo dont mind you using it because it was made by them the mode can unbrick a semi-bricked wii thats why your console has it because they always repairing semi-bricked wiis its third parties what do the damageby ilovehomebrew - Software
i know what it is im not guessing knew about it before it was invented its the same mode as safe mode for pc my dad works for nintendo its completly harmless does fix your message board and other things theres nothing new in maintenance mode it can unbrick a semi-bricked wii sorry if im flooding your forum im trying to think of the info i know it cant unbrick a full-bricked wii ds has got tby ilovehomebrew - Software