Car Stereos: hooking up rca input converter, scotch lok, rca input

Question
how many wires do i hook up because there are five wires.can u help me?

Answer
Hi Marcus,

Most basic 2-channel line-out converters will have these wires:

left speaker (+)
left speaker (-)
right speaker (+)
right speaker (-)
ground

The left speaker wires (on the converter) are usually white or green; right speaker wires will usually be gray or violet.  

The four speaker wires need to be connected to the matching factory speaker wires. (The colors won't match; you may have to find a wire color guide for your car).  You don't have to disconnect the factory speakers; just tap the converter's wires into the factory wires, by stripping away some of the insulation without cutting it, or by using a connector like a "Scotch-lok" or T-tap.  It's important to keep the (+) and (-) wires straight; if you mix them up on one side, it will affect the sound quality.

The fifth wire, ground, usually doesn't need to be connected to anything.  In theory, if you get excessive noise through the converter, you can try connecting this wire to the vehicle chassis metal; but I've never had to use it.

Hope this helps!

Brian