Article 1. General Provisions of California Vehicle Code >> Division 12. >> Chapter 2. >> Article 1.

During darkness, a vehicle shall be equipped with lighted lighting equipment as required for the vehicle by this chapter.

Any requirement in this chapter as to the distance from which any lighting equipment shall render a person or vehicle visible or within which any lighting equipment shall be visible shall apply during darkness, directly ahead upon a straight, level unlighted highway, and under normal atmospheric conditions, unless a different time, direction, or condition is expressly stated.

(a) All lighting equipment of a required type installed on a vehicle shall at all times be maintained in good working order. Lamps shall be equipped with bulbs of the correct voltage rating corresponding to the nominal voltage at the lamp socket.
  (b) The voltage at any tail, stop, license plate, side marker or clearance lamp socket on a vehicle shall not be less than 85 percent of the design voltage of the bulb. Voltage tests shall be conducted with the engine operating.
  (c) Two or more lamp or reflector functions may be combined, provided each function subject to requirements established by the department meets such requirements.
  (1) No turn signal lamp may be combined optically with a stoplamp unless the stoplamp is extinguished when the turn signal is flashing.
  (2) No clearance lamp may be combined optically with any taillamp or identification lamp.

(a) All motor vehicles manufactured and first registered after January 1, 1970, shall be equipped so all taillamps are capable of remaining lighted for a period of at least one-quarter hour with the engine inoperative. This requirement shall be complied with by an energy storing system which is recharged by energy produced by the vehicle.
  (b) All motorcycles manufactured and first registered after January 1, 1971, shall be equipped so all taillamps, when turned on, will remain lighted automatically for a period of at least one-quarter hour if the engine stops.

Whenever a requirement is declared as to the mounted height of lamps or reflectors, the height shall be measured from the center of the lamp or reflector to the level surface upon which the vehicle stands when it is without a load.

(a) A vehicle may be equipped with a system to supplement the driver's visibility of the roadway to the front or rear of the vehicle during darkness. This system may incorporate an illuminating device that emits radiation predominantly in the infrared region of the electromagnetic spectrum and a display monitor to provide an image visible to the driver of the vehicle. The system, or any portion of it, shall not obstruct the vision of the driver, and shall not emit any glaring light visible in any direction or to any person. The illuminating device may be mounted inside the vehicle, if it is constructed and mounted so as to prevent any direct or reflected light, other than a monitorial indicator emitted from the device, from being visible to the driver.
  (b) The system shall be operated only with the headlamps lighted. An illuminating device for the system shall be interlocked with the headlamp switch so that it is operable only when the headlamps are lighted.
  (c) (1) No part of the illuminating device may be physically or optically combined with any other required or permitted lighting device.
  (2) The illuminating device may be installed within a housing containing other required or permitted lighting devices, if the function of the other devices is not impaired thereby.