Hi
Thank you for the suggestions. Unfortunately, I haven't been able to find the song. I saw the video of the ad, but it wasn't the one that includes the song. In fact that ad (the video on the right) was the first among the alien series of toyota. In my country they aired that ad, but using a different song. So I am guessing that even if you had seen the ad I described, you still wouldn't be able to know the song, cause they probably change them from country to country.
It's definitely a pop song, very modern. A male is singing, I doubt he is a solo artist, I think he belongs to a group. If only I knew the correct lyrics, but to me it sounds like he's saying: "hey mister grey, what are you..."
Aaaaah it's a nightmare, I'm obsessed with it... I won't rest till I find it! Perhaps I should email toyota about it : -P