Needing some help. I'm modifying my mazda 2 2004 head unit. I managed to get an aux lead to 3.5m jack which activates & plays music. Now I'm looking to attach a module that decodes & plays MP3s from TC Card/USB stick, Aux in or Bluetooth. It works, however i'm hoping to tidy up the wiring by having it draw power from the aux port. Now, I've attached an image I've found on google which shows the connectors my aux cable uses. But I'm wanting to know what the other pins are for, which are the power +/- & GND pins so I can draw power directly from the head unit & not from the 12v port.

I've tried to google & it does show up images of diagrams. But the images are blurred out with photobucket branding & I don't know why, maybe the images no longer available & it's cached or something.

Anyways, any help would be much appreciated.