Aftermarket car audio wiring harnesses use a standard color code to identify what the wire is used for.  Understanding what these colors mean can make your installation faster, easier, as well as ensuring that your installation is done properly.  It is important that the appropriate cables are connected properly to the cables that they are intended to.  Failure to properly connect wires can potentially result in damaging the components and voiding warranties.  Below is the standard color guide for aftermarket car stereo wiring harnesses:

Wire Color Wire Function
Yellow 12V Constant / Memory
Red Switch / Accessory
Black Ground
Blue Antenna Remote
Blue with White Stripe Amplifier Remote Turn-on
Orange with White Stripe Dash Light Dimmer/Illumination
Green Left Rear Speaker (+)
Green with Black Stripe Left Rear Speaker (-)
White Left Front Speaker (+)
White with Black Stripe Left Front Speaker (-)
Purple Right Rear Speaker (+)
Purple with Black Stripe Right Rear Speaker (-)
Gray Right Front Speaker (+)
Gray with Black Stripe Right Front Speaker (-)

Keep in mind that this guide applies specifically to most aftermarket applications.  Your vehicle’s factory OEM wiring is very different from the above colors and they will not match the colors mentioned above.  For this reason special wiring harnesses are made to easily connect to factory harnesses without having to worry about matching colors.  Please always check the wire coloring codes on your components before installing them.