Is it this unit??
Pioneer USA - Pioneer
If so, it states in the spesifications for the DEH-P6000UB: "Built-in Auxiliary Input - Built-in (Rear)", without stating wich type of connection there is (RCA/minijack or other). But it looks like you could do it the same way I did.
From the picture of that unit it seems that it has RCA plugs in the rear. Then it should be easy to make a plug for this. I have not searched for pre-made harness for this as I made this easy myself.
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Honda Jazz 1.4L CVT '07 (GD1) in Black Amethyst Pearl.
Sports styling; Front and rear bumper, skirt and roof spoiler. Foglights.
Tinted windows. Pioneer AVIC-HD3BT. Mugen style grill. Tail gate garnish. Altezza tail lights.
Momo FXL-One 17x7 Wheels with Cooper Zeon 2SXH 205/40R17 tires. Maybe JDM front next?
http://www.flickr.com/photos/f0nix/s...7604094670434/