QuestionOk, I am the proud owner of a 1976 Chevrolet Custom Deluxe pick up. I was given a perfectly good Alpine CDM-7874 Head Unit. The problem is, in the truck there are not enough wires run for the stereo. More specifically, the stock stereo only needs a power lead wire and a ground wire to function. I have two brand new Pioneer 6x9 four channel speakers hooked up to the stock stereo. I have found wires from the back of the fusebox on the firewall in the cab that match the colors of the wires on the back or the head unit but they run to the dash. My question is, are those the wires that i need to splice into to hook up the stereo? And if not, where are the ones i need to use? Thank you.
AnswerHi Tom,
Your current wiring should include an accessory (key-switched) power wire, and a ground wire. Other than the speaker wires, the only additional connection you need is a constant voltage source (one that doesn't switch off with the key). Probably the easiest place to find this is the orange wire at the back of your truck's cigarette lighter. Otherwise, trucks like yours usually have tap points in the front of the fuse box, made specifically for adding additional accessories; you could route a wire from the head unit directly to the fuse box. (Be sure to put your own 15-amp fuse on the wire, near the tap point in the fuse box, if you do this).
Your Alpine deck's wire colors should work like this:
Yellow: constant power source
Red: Key-switched power source (probably yellow in the GM radio wiring)
Black: chassis ground
Orange: Illumination. This is meant to be connected to a wire that supplies voltage whenever your parking lights are turned on. This connection is not necessary for the head unit installation; it's just meant to dim your display at night. You may be able to find a brown illumination wire in the factory radio harness, or at the light switch.
Blue and blue/white: Not required for your installation.
Hope this helps!
Brian
