Ok I am installing a new head unit in my car, this valor HU has been in the car since the original owner dropped 4k into the sound system, I have since stripped it down to just the 4 main speakers with two tweeters. Now my question how do I go about hooking up the factory subs/speakers to my new aftermarket unit.
I don't think the car was originally wired with either of the shaker HU, as the wires for the subs are tied off in the door. The HU I'm installing is the Sony XAV-64BT. From what I have heard the door subs are not very good at all, I am just looking for a little extra bass in the car, since my Rockford 6X8's put out some pretty good mid/high.

 

If someone dropped $4k into a system and ran it off a valor deck, something isn't right.

installing thenew one is as simple as pulling the deck out, cutting the hrns off of the old radio and using it for the new one. Connect red to red, yellow to yellow, ect..

 

That does seem a little sketchy....