color code for wires

[oasis100]

Hi,
This audio question is not for a mercedes, it's for a 2002 Jetta .
I'm installing a deck without buying a wire harness that plugs into the cars stereo plugs.

So basically, im' cutting the connectors from the car and attaching right to the wire harness that comes with the HU.

I remember someone posted a site where I could check something like this up. I need to know the wire codes for the cars stereo. I've figured out the speaker wires, but I'm not sure about the power wires.

thanks for any help.