Utah Code § 41-6a-1603: Lights and illuminating devices -- Duty to display -- Time.

(1)

(a) The operator of a vehicle shall ensure the lamps or lights of the vehicle are illuminated while the vehicle is being operated on a highway at any time:

(i) from sunset to sunrise; or

(ii) when persons and vehicles on the highway are not clearly discernible at a distance of 1,000 feet ahead due to:

(A) insufficient light; or

(B) unfavorable atmospheric conditions.

(b) An operator of a vehicle driving with automated lights does not violate Subsection (1)(a) if:

(i) the vehicle's automated light function is operable and engaged; and

(ii) the automated feature has not been overridden or adjusted.

(c) The lights, lighted lamps, and other lamps and illuminating devices under Subsection (1)(a) shall be lighted as respectively required for different classes of vehicles, subject to the exceptions for parked vehicles under Section 41-6a-1607.

(2) Whenever a requirement is made as to distance from which certain lamps and devices shall render objects visible or within which the lamps or devices shall be visible, the provisions apply during the times specified under Subsection (1)(a) for a vehicle without load on a straight, level, unlighted highway under normal atmospheric conditions, unless a different time or condition is expressly stated.

(3) Whenever a requirement is made as to the mounted height of lamps or devices it shall mean from the center of the lamp or device to the level ground upon which the vehicle stands when the vehicle is without a load.

(4) A violation of this section is an infraction.