Originally Posted by
Richard Cranium
You can - but how long will speaker wire last if used or left outside in the Winter? Don't you think for something as important as a turn or brake light you ought to do it right?
Agreed.
Speaker wires are mostly PVC insulated jacket. I think they are rated for 50-100v which should be no problem on a 12v system. However the jacket are not listed the same as regular electrical wire. Wire have listing such as THHN or THWN. Thermoplastic, high heat or high water and nylon coated. Their properties give the insulation more weather, oil, solvent, gasoline resistant. So aftersome outdoor beating, speakerwire may start to deteriorate and have insulator crack.
Instead of Radioshack, is there a Homedepot, Orchard supply or Lowes nearby? They will have what you need.