Best Answer: Your positive cable is the red cable it will also have + sign on the battery. The negative cable is the black cable and it will have a - sign on the battery. A car battery has + or - sign as well as color on each of its two terminal posts. The terminal post with a red ring and a + sign is the positive and usually located on the right side of the unit while the terminal post with green/black color with - sign is the negative and is located in the left side of the positive post.