Most factory radios in cars don’t include a line in. alfaGato decided he wanted to integrate an iPod into his system, but wanted to maintain the factory functions. His Saab 9-3 came with GM’s OnStar system (not activated) which he thought would make a decent in road into the radio. His instructions should work for most radios with a factory cellphone integration option. He opened the radio and cut the traces for the phone input to get separate left and right channels. These were wired to the external CD changer input. He didn’t have the factory changer and the phone input also had amplification on the line that would interfere with the iPod. He designed a circuit with two possible inputs: iPod connector or AUX. The circuit is designed to mute the inputs if OnStar is activated. The circuitry is contained within a Saab factory phone mount with an iPod holder attached to it. Check out alfaGato’s blog dedicated to the project and our previous auxiliary input projects.