What color is the positive car battery terminal?

The post is just lead, gray color. The cable is sometimes colored red. The battery could also have a "+" symbol to mark positive.

Red

Both posts are gray, positive has a red wire running to it, and a plus sign next to it.

Normally red or brown. The battery has a + stamped into it by the positive terminal. Follow the wires, on a modern car the positive will go to the alternator and starter. The negative wire (easier to...

Positive is either red or has a "+" symbol.