head unit problems

[chrisiseffincool]

I just bought a new Pioneer head unit (w/ harness) and I'm trying to wire it to my current system. Before, I had a Kenwood head unit and when I took it out (the guy who had my car before put it in) it looked all nig-rigged. I started out doing a pigtail twist to connect the wires followed with some duct tape, and I'm almost positive each wire was going to the correct wire, but it still didn't work. I'm also having trouble grounding it seeing as there are no good grounds in the back of my dash. Before there was a blue wire that went straight to the whole fuse panel on the left side of the car, but that's not there anymore. I'm really just at a loss and don't know how to wire it correctly..any tips/suggestions? I'm trying to find a good diagram to see which colors are what on my 2002 VW GTI 1.8T.

Here are some pictures but they probably won't help. Just thought they would be better than nothing:

http://img585.imageshack.us/i/20101201145148.jpg

http://img689.imageshack.us/i/20101201145157.jpg

http://img213.imageshack.us/i/20101201145227.jpg

[casemods]

So what are you trying to hookup? The speakers to the head unit?

For that, just take the speakers out and look at the wire color.

Is it all stock wiring behind the head unit? Look up your make and model and find the wiring diagram.

I don't know why they put such crappy wiring in cars...