All, i watched 5 videos all telling me to "trip A", foot off brake, hold kph/mph button, double tap power switch. That didn't work. i used trip b, odometer, start in kph mode, nothing. Then, i put it in "Trip A" with foot ON brake. Guess what? Cleared message. Wth? I hope this helps someone. (I suppose i should update my profile, but i never ask stuff, or answer stuff. This is a 2012 Prius now, all the bells and whistles, i'm VERY happy with it over the old one)
In your profile, Prius 2015, now you are writing about Prius 2012, the topic is about Prius V? There is a mistake somewhere.
How to turn off the maintenance required warning is shown in detail in the owners manual. If you do not have a printed copy to look at, you can download the PDF version of the owners manual online. Then, take some time and read the manual to learn about your 2012 Prius.