Regulations for fitting work lights to O3 or O4 vehicles

The various options for adding extra work lights

As manoeuvring lights have also been permitted under European type approval for several years now, there are quite a few options available when it comes to additional work lights on O3 and O4 vehicles. For example, you can add extra reversing lights, manoeuvring lights or standard work lights. Nevertheless, in practice, the installation of additional lights still causes a fair amount of confusion. What type approval must the chosen light have? And can you simply have these lights automatically linked to the reverse gear? The answer depends heavily on the desired light function and the chosen approval route: European type approval (factory-fitted) or surface mounting (aftermarket).

In this article, you can read about the laws and regulations governing work lights designed to provide extra light when reversing or during loading and unloading. We also explain what the AR and ML codes on the lights mean and what the regulations mean in practice for trailer manufacturers and bodywork companies.

Option 1: Ex-works with European type approval

Are you building a new O3 or O4 semi-trailer that is being placed on the market via a full European type approval (WVTA)? If so, you may install manoeuvring lights, work lights or additional reversing lights subject to certain conditions, which we explain in more detail below.

Work lights

Trailer manufacturers can include additional side or rear lights within the European type approval (WVTA) as work lights, intended to illuminate the area around the vehicle whilst work is being carried out. This offers a relatively high degree of flexibility regarding the number and mounting position of the lights. Work lights serve a different purpose to reversing lights (AR) or manoeuvring lights (ML): they are intended to illuminate a work area or activities around the vehicle. The specific requirements for the use of work lights may also depend on national regulations.

Additional manoeuvring lights on the side

Since the entry into force of UN Regulation No. 48, Revision 14 – Amendment 2, manoeuvring lights under UNECE R48 have also been permitted on trailers and semi-trailers. A strict requirement here is that the lights used must have a valid ECE R23 or ECE R148 approval in accordance with the official type-approval documentation, and that the corresponding function code ‘ML’ must be permanently marked on the light itself (on the glass or the housing). Without this official certificate and the physical marking, the light must not be used for this function.

How many manoeuvring lights are you allowed to fit?

• For vehicles up to 6 metres in length: 1 or 2 lights (maximum 1 per side).
• Vehicles between 6 and 9 metres in length: a maximum of 4 lights (a maximum of 2 per side).
• Longer than 9 metres (most O4 semi-trailers): a maximum of 6 lights (a maximum of 3 per side).

Requirements for the fitting of manoeuvring lights

• The lights: Must be officially certified in accordance with ECE R23 or ECE R148 and permanently marked with the function code ML on the housing or the lens.
• The electrical circuit (Section 6.26.7): The manoeuvring lights on the trailer must never be able to be activated unless the semi-trailer’s position lights are switched on.
• Activation conditions: The law permits automatic activation when reverse gear is engaged, when a reversing camera system is activated, or when a slow forward manoeuvre is initiated.
• Speed signalling: As these lights may also be illuminated during forward manoeuvres, UN Regulation UN R48 stipulates that they must switch off automatically as soon as the forward speed of the trailer exceeds 15 km/h. This switch-off must be controlled via a speed signal sent directly from the trailer (usually via the EBS system).

Source: UNECE, UN Regulation No. 48, Revision 14 – Amendment 2, E/ECE/324/Rev.1/Add.47/Rev.14/Amend.2, paras. 6.26.1 and 6.26.7, which came into force on 5 June 2023.

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Additional reverse lights at the rear

Two additional lights may be fitted to the rear of an O3 or O4 category vehicle, which are activated as reversing lights. This is subject to the lighting being R23- or R148-certified and bearing the AR symbol, which stands for reversing lights. In addition, the fitting regulations set out in ECE R48 apply.

Additional side reverse lights

As an alternative to rear mounting, both the UNECE R48 regulation and the RDW MOT handbook permit these two additional reverse lights to be mounted on the sides of the vehicle (one on the left and one on the right). The lights used must be explicitly certified for this function and bear the AR code. A standard wide-beam work light or a light with an ML code (manoeuvring light) is prohibited for this automatic switching on the reversing circuit. Speed-controlled EBS switching is not required in this case.

The function symbols AR and ML

The glass of the approved light must always bear one of these function codes alongside the standard (R23 or R148):

1. Function code AR (reverse light): these lights have been tested to emit a powerful beam of light directly to the rear. They may, however, switch on automatically when reverse gear is engaged.
2. Function code ML (manoeuvring lamp): these lights have a very different light distribution (up to 500 candelas all round) and primarily direct the light at an angled angle downwards to prevent glare. They must never be connected to a standard reversing circuit unless the vehicle is fitted with a speed-controlled cut-off system.

In practice, additional work lights are fitted to a wide variety of O3 and O4 semi-trailers. These include refrigerated semi-trailers, curtain-sided semi-trailers, tank and silo trailers, tipper semi-trailers, container chassis, distribution and city trailers, heavy centre-axle trailers, tipper trailers and (semi) flatbeds. The additional lighting is mainly used to provide better all-round visibility around the trailer during manoeuvring, loading, unloading or working in the dark.

Route 2: Retrofitting in the workshop (bodybuilding)

Manoeuvring lights not permitted
If there is a need for additional work lights during the surface mounting of a vehicle, you must refer to national legislation. This often leads to confusion, as these do not immediately incorporate the latest amendments to the European ECE R48 regulation. For example, manoeuvring lights (ML) for semi-trailers/trailers are often not yet specifically permitted under national regulations, and this leads to rejection, as inspectors base their decisions on the regulations in force in the country concerned.

To fit an O3 or O4 semi-trailer with this additional lighting, many bodybuilders choose to install and specify the lights as work lights. Unlike manoeuvring lights, work lights are explicitly permitted on O3 and O4 semi-trailers, provided the basic regulations are complied with.

European type approval and national requirements

Whilst new developments are sometimes already incorporated into WVTA (European whole-vehicle type approval), this may not yet have been adopted at national level. This often takes more time. A good example is the Signal Road Projection, about which we have written an article. With regard to work lights, whilst manoeuvring lights may be retrofitted to a truck (N2/N3), they often still result in a vehicle being rejected for O3/O4 semi-trailers because this has not yet been implemented in national legislation. Below are the options that are permitted:

Additional reversing work lights on the side or rear: activated when reversing

What is permitted, however, are two additional reverse lights on the side or rear of the semi-trailer (one on each side).

• The circuit: may be automatically activated when reversing.
• Requirements: the light used must have R23 or R148 approval with the function code AR. A standard work light or ML manoeuvring light is therefore not permitted.

Additional work lights on the side or rear: not activated when reversing

Would you like to fit universal LED work lights to provide the driver with optimum all-round visibility around the trailer ? This is permitted, provided they are specified and used as work lights.

• The circuit: must be operated completely independently and manually (via a switch on the chassis or a switched PIN to the cab). The lights must never come on automatically when reverse gear is engaged.

If, as a surface mount engineer, you opt for the flexible option of manually operated work lights, please ensure the end user is fully informed about the conditions of use. A manual switch does not, in fact, constitute a licence for unrestricted use whilst driving on public roads:

• 🇳🇱 Netherlands: work lights are permitted on trailers. However, their use must not cause a nuisance or dazzle other road users.
• 🇩🇪 Germany (Section 52(7) StVZO): completely prohibits the use of work lights whilst driving. When stationary on a public road, however, they may be switched on for loading and unloading operations, provided they do not dazzle other road users.
• 🇬🇧 United Kingdom (RVLR 1989, Reg. 27): use is permitted solely for lightening an immediate working area, an accident or a breakdown. Use whilst driving normally on public roads constitutes an offence.
• 🇧🇪 Belgium, 🇫🇷 France & 🇮🇹 Italy: white light that shines to the side or rear whilst on public roads is not permitted and may result in fines or the vehicle being rejected in a roadworthiness truck.

Fitting additional reversing lights

The key here is to do this safely without overloading the electrical system. Read all about it in the article on fitting additional reversing lights.

Drawing up a well-thought-out lighting plan

Fitting additional side lighting to an O3 or O4 semi-trailer requires a clear plan in advance. If, as a semi-trailer manufacturer, you are working within a European type approval for manoeuvring lights, ensure you have the required speed-controlled circuit and ML-certified lights. Are you specialising in retrofitting in the workshop? Then opt for an independently switched work light or use side reverse lights with a valid AR function code.

View our full range of ECE R148-certified lighting for bodybuilding.

The difference between ECE R23 and ECE R148

• ECE R23: this is the old regulation that specifically applied to the testing of reverse and manoeuvring lights.
• ECE R148: this is the new central regulation for signal lighting (LSD). Previous individual regulations (such as R23, but also R91 for side marking) have been consolidated into this single regulation. Under both the old and the new standard, the light must be tested for a specific function.

Who sets the regulations for vehicle lighting?

Watch the TRALERT® video on UN ECE standards and legislation for a visual explanation of how these regulations work.

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Disclaimer:

At TRALERT®, we do our best to keep the information in this article as accurate and up-to-date as possible, including the regulations surrounding vehicle lighting. However, legislation can change regularly, and although we make every effort to implement these changes in a timely manner, it is possible that certain updates or adjustments have not yet been incorporated into this article. We therefore always advise our readers to check the current legislation with their local government or regulatory bodies, especially when it comes to exceptions or specific national regulations. TRALERT® is not liable for any damages or fines resulting from outdated or incomplete information in this article.

If in doubt, always contact the competent authority to ensure that your vehicle meets all legal requirements.