Wisconsin Statutes Vehicles (Ch. 340 to 351) § 347.06. When lighted lamps required

(1) Except as provided in subs. (2) and (4), no person may operate a vehicle upon a highway during hours of darkness or during a period of limited visibility unless all headlamps, tail lamps, and clearance lamps with which the vehicle is required to be equipped are lighted. Parking lamps as described in s. 347.27 may not be used for this purpose. This subsection does not apply if lamps that are automatically activated whenever the vehicle is started are in use, if the headlamps are of sufficient intensity to satisfy the requirements for daytime running lamps under 49 CFR 571.108, S7.10.13.

(2) Headlamps need not be lighted on a towed vehicle or on a vehicle having at least 2 lighted adverse weather lamps on the front thereof and being operated under the circumstances described in s. 347.26(3)(b).

(3) The operator of a vehicle shall keep all lamps and reflectors with which such vehicle is required to be equipped reasonably clean and in proper working condition at all times.

(4) A duly authorized warden, as defined in s. 24.01(11), may operate a vehicle owned or leased by the department of natural resources upon a highway during hours of darkness or during a period of limited visibility without lighted headlamps, tail lamps, or clearance lamps in the performance of the warden's duties under s. 29.924(2).