question on head unit installation. Options

[Zimluura]

hey, i recently got a new pioneer premier DEH-P680MP head unit and i really like it.

when i was hooking it up there wasn't a blue cable to go to the antenna. so i left that hanging. but now my antenna doesn't go up when i switch it to radio. so anyways, i'm now noticing that the installation instructions say something about the blue & white wire that had a little remote label on it.

they say: "To system control terminal of the power amp or Auto-antenna relay control terminal (max. 300mA 12V DC)"

so i'm thinking maybe i want to hook that up to the blue antenna cable.
does this sound like a good idea? or does this sound like a really really dumb thing to do?

thanks in advance
ny