I just installed a double din to replace the factory radio. The unit comes with two special cables labeled as SW1 and SW2 in which according to the instructions you can use them to program any of your steering wheel controls. I want to use them to control the volume and next track, so my questions are: 1) where is the volume cable behind the radio? 2) Does the volume up and volume down use a separate cable? 3) Where is the cable for next track? If anybody can provide the schematics or help is greatly appreciated.

Thanks,

DominicanJB