A. Any motor vehicle, trailer, or semitrailer which is so constructed or carries a load in such a manner as to prevent a hand and arm signal required in § 46.2-849 from being visible both to the front and rear of such motor vehicle, trailer, or semitrailer or any vehicle the driver of which is incapable of giving the required hand and arm signals, shall be equipped with electrical turn signals which meet the requirements of this title and are of a type that has been approved by the Superintendent. A tractor truck, however, need not be equipped with electrical turn signals on the rear if it is equipped with double faced signal lights mounted on the front fenders or on the sides near the front of the vehicle clearly visible to the rear.
B. It shall be unlawful for any person to drive on any highway a motor vehicle registered in the Commonwealth and manufactured or assembled after January 1, 1955, unless such vehicle is equipped with such turn signals on both front and rear.
C. Any such turn signal may be used in lieu of the hand and arm signal required by § 46.2-849.
D. Subsections A and B of this section shall not apply to any motorcycle. The provisions of this section shall not apply to motor vehicles, trailers, or semitrailers used for agricultural or horticultural purposes and exempted from registration under Article 6 (§ 46.2-662 et seq.) of Chapter 6 of this title.