Extra connection.
However, unless the installer of the Pioneer head unit completely rewired the entire audio system, the primary connectors would still be in use. Even if they went with an aftermarket amp and speakers, the two power wires, ground wire, dash illumination wire, steering wheel controls, along with the power antenna (Firebird) or speed controlled volume (Camaro) would still be used. Usually an adapter harness is connected to the aftermarket head unit so that it plugs into the factory connector.








