Abstract: An illuminated traffic control sign transforms a conventional passenger automobile into a traffic control vehicle. The body of the sign is formed from a flexible sheet of weather resistant material. The sign is ordinarily stored under the luggage compartment lid of the automobile when not in use and is deployed between the open lid and the lower part of the luggage compartment when in use. The flexible sheet has a horizontal double arrow design formed on it in a color that contrasts with the color of the sheet. Electric light fixtures are attached over the double arrow design to illuminate the design when the fixtures are activated. A plurality of flaps are secured to the flexible sheet and may be moved between retracted positions where they reveal the double arrow design or active positions where they cover part of the design. By positioning the flaps, the double arrow design may be selectively changed to a right arrow, a left arrow, or a caution bar without an arrowhead.