Number of driving lamps required or permitted.

(a) At all times specified in § 4331 of this title, at least 2 lighted lamps shall be displayed, 1 on each side at the front of every motor vehicle other than a motorcycle or motor-driven cycle, except when such vehicle is parked subject to the regulations governing lights on parked vehicles. (b) Whenever a motor vehicle equipped with head lamps as required in this subchapter is also equipped with any auxiliary lamps or a spot lamp or any other lamp on the front thereof projecting a beam of intensity greater than 300 candlepower, not more than a total of 4 of any such lamps on the front of a vehicle shall be lighted at any 1 time when upon a highway.