Wires and lots of them! You open up the dash and all you see is a rainbow of colored strands that disappear into the inside of your car. It can be a daunting task to whip out the multi-meter and begin to test each wire in your vehicle to try and figure out what they do. Luckily,wiring harnesses  are here to save us from the hassle. There are different variations of harnesses, so I will give you a brief overview of the generic types;

Metra 70-5519

Standard Ford Wiring Harness – Metra 70-5519

Standard Wiring Harness (Connects to factory plug): Standard wiring harnesses are available for almost all vehicles. They plug into the factory plug of the vehicle, so you do not have to cut it off when you wire up your new aftermarket radio. These harnesses allow for a quick and clean install and you can re-install your factory radio at any time. For example, the Scosche FD16Bharness works for most Ford vehicles, providing a hassle free install.


Reverse Wiring Harness (Connects to factory radio): This harness is a reverse form of the standard wiring harness and plugs into the factory radio. It is used to restore the factory radio plug if it has been damaged or removed so you can install your stock radio again.

Stereo Relocation Harness:  Some vehicle radios integrate heavily with the vehicle. For example, some Chevrolet and GMC vehicles warning lights and chimes go haywire once the radio is removed. This relocation harness allows you to keep the stock radio and move it to another location. In its place you can add an aftermarket radio without worrying about losing any vehicle functionality.

Amplifier Integration Harness: If you ordered the advanced sound system package with your vehicle, it may have come equipped with a factory amplifier that supplies power to your speakers and even a subwoofer. Once you replace the factory radio, the amplifier will cease to function without an integration harness. These harnesses allow you to keep the factory amplifier when installing an aftermarket radio.

PAC OS-311B

Premium GM Wiring Harness – PAC OS-311B

Amplifier Bypass Harness: If your vehicle came equipped with a factory amplifier that supplies power to your speakers and even a subwoofer, this bypass harness allows you to easily disconnect the amplifier and bypass it all together. With the amplifier out of the picture, you can use an aftermarket amplifier or use the aftermarket receiver’s built-in amplifier to power your speakers.

Chime Retention Harness: Later GM vehicles have factory warning chimes that alert the driver of possible vehicle issues, when doors are open or if the lights are left on. When replacing the factory radio, these chimes no longer function. A chime retention harness enables the installation of an aftermarket radio without retaining the factory radio while keeping the vital warning chimes.

Premium Harness:  Vehicles with specialty services, such as GMs On-Star service, or factory amplifiers require premium harnesses to accommodate these features. The most common would be a GM harness that retains the Bose factory amplifier, On-Star, and warning chimes such as the Scosche GM09SR.

Speaker Adapter Harness: Car manufactures create specialty speaker connectors to interface with factory speakers. When replacing these speakers, this specialty connector must be cut. With a speaker adapter harness, you can add aftermarket speakers while keeping the factory plugs.

Vehicle Wire Harness