12vDC cable: The white stripe indicates the + or - wire Jan 14, 2008Title says it all. I gotta splice a cigarrete lighter adapter cable from something onto something else, and without a volt meter, how do i tell which of the two cables is the positive? One has a white stripe on it, the other doesn't, and i know that means it's one or the other, but not knowing which, it does me no good. So what does the white stripe on a black two-wire dc power cable mean?Status: OpenAnswers: 3Usually the stripe means + but to be sure without a meter I use items that are not polarity sensitive such as a light bulb. By placing one side on..Best answer · 0Without a meter it can be very hard. I have seen Cig. lighter adapter wired differently from what you would think. Tech1 has a good solution.0Black And White Cable0 Striped Tracer Wire - Sherco Auto & Marine Supply Sherco Auto & Marine Supply's Striped Marine Tracer Primary Wire is constructed from Type III Class K tinned copper. It is then jacketed with a durable, flexible, high quality PVC insulation.