The quest is unlocked after completing The Future of Hyrule scenario.
"You've been tasked with asking Koroks all over Hyrule if they know about parts for Terrako's repair. Gather the fun-loving Koroks by throwing a hoppin' dance party!"
"News of your dance party spread far and wide, and lured Koroks from all over Hyrule. Based on the gossip you gleaned at the dance, you found parts that might revive Terrako!"