§ 393.23 Power supply for lamps.

PART 393—PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION, last amended 2016-12-12

All required lamps must be powered by the electrical system of the motor vehicle with the exception of battery powered lamps used on projecting loads.

Official text from the eCFR. The eCFR is an authoritative but unofficial editorial compilation; the Federal Register is the legal source.