56.3. Which external lighting devices must be switched on on the trailer of a road train while driving at night and in conditions of insufficient visibility?
UAЯкі зовнішні світлові пристрої обов'язково повинні бути ввімкнені на причепі транспортного складу (автопоїзда) під час руху в темний час доби і в умовах недостатньої видимості?
This exam question from the Traffic Rules of Ukraine concerns driving safety at night and in conditions of poor visibility, when other drivers must clearly see not only the tractor unit but the entire vehicle combination. Proper use of external lighting devices reduces the risk of rear-end collisions and mistakes in estimating the length and dimensions of the road train, especially when driving in fog, rain, snowfall, or at dusk.
The question tests knowledge of the section of the traffic rules regarding the use of external lighting devices (paragraph 19.1 of the Traffic Rules). In these conditions, a separate requirement is established for trailers and towed vehicles: they must be marked with position lamps so that their outlines are visible to other road users. This is what you need to remember for the theoretical exam, as the rule clearly distinguishes what is switched on the motor vehicle (headlights) and what exactly on the trailer (position lights).
Analysis of the answer options in the tickets usually comes down to understanding the necessity and purpose of the devices: position lamps on the trailer are always required when driving in the dark and in poor visibility, because they indicate the dimensions of the road train. Rear fog lamps are not universally mandatory for every trailer and do not replace the requirement for position lights, while hazard warning lights are used in other situations (stop, forced stop, emergencies) and are not intended for normal driving. The wording "position lamps or rear fog lamp" is also incorrect, as the Traffic Rules of Ukraine do not offer a choice: the trailer in a road train must be marked specifically with position lamps.
Clause 19.1
At night and in conditions of insufficient visibility, regardless of the degree of road illumination, as well as in tunnels, the following lighting devices must be switched on on a moving vehicle: a) on all motor vehicles — dipped (main) beam headlights; b) on mopeds (bicycles) and horse-drawn carts (sledges) — headlights or lanterns; c) on trailers and towed vehicles — side marker lamps. Note. In conditions of insufficient visibility, it is allowed to switch on fog lights instead of dipped (main) beam headlights on motor vehicles.
Clause 1.10 (term "Trailer")
Trailer — a vehicle designed to move only in combination with another vehicle. This type of vehicle also includes semi-trailers and dolly trailers.
Clause 1.10 (term "Road train (vehicle combination)")
Road train (vehicle combination) — a motor vehicle coupled with one or more trailers by means of a coupling device.
Clause 1.10 (term "Night time")
Night time — the part of the day from sunset to sunrise.
Clause 1.10 (term "Insufficient visibility")
Insufficient visibility — road visibility in the direction of travel of less than 300 m in twilight, fog, rain, snowfall, etc.
Therefore, the correct answer is "Side marker lamps," considering that according to clause 19.1 (c) of the Traffic Rules, at night and in conditions of insufficient visibility, side marker lamps must be switched on on trailers (as part of a road train).
A trailer is a vehicle that moves only together with another vehicle, forming a road train (autotrain). At night (from sunset to sunrise) and in conditions of insufficient visibility (when the road in the direction of travel is visible for less than 300 m, for example in fog, rain, or snowfall), it is especially important that all elements of the road train are visible to other road users.
Clause 19.1 of the Traffic Rules distinguishes which lighting devices must be turned on for different types of vehicles when driving in such conditions. For a motor vehicle, these are usually the headlights, but for a trailer, a separate requirement is established: it must have its position lights turned on.
The logic of this rule is simple: the trailer does not have its own headlights to illuminate the road, but it is part of the road train and must be marked on the road by its dimensions and position. For example, at night, the driver behind must clearly see the dimensions of the trailer to correctly assess the length and width of the road train and safely maintain distance.
Therefore, the correct answer is "Position lights," because according to clause 19.1 of the Traffic Rules, at night and in conditions of insufficient visibility, the position lights must be turned on on the trailer while driving to mark it on the road.