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How to Fit LED Lighting to Your Car Legally

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You install LED lighting within your house - so why not your car? Here are the most common questions on the topic of LED lights for cars, fielded by GEM’s Technical Department:

1. New cars are fitted with LED lamps, why can't I?

LED lamps, fitted to new cars, have been tested and pass EU Whole Vehicle Type Approval. This means that the lenses and light sources work together to optimise driver visibility and reduce dazzle to oncoming traffic.

So, are LED headlights legal in the UK? They are, because these new car LED lamp units pass European / UNECE technical standards. This is the same with other lamps, including those fitted to the side and rear.

Nonetheless, the ‘bulbs’ on those newer cars thus equipped, at the time of writing, cannot be renewed. If an LED light source fails, the whole lamp has to be replaced.

You may have noticed LED replacement bulbs on the market. These are designed to be fitted into halogen lamps that accept filament bulbs. Unlike replacement, road-legal filament bulbs, LED conversion bulbs fail to comply with the aforementioned European technical standards for many reasons, so they cannot be e-marked.

Fitting them ensures that your lamp will not perform as designed and will prejudice the Whole Vehicle Type Approval of your vehicle, making it unroadworthy. This is why sellers tend to state that their LED bulbs are sold for off-road use only.

2. My car has passed its MoT Test with an LED bulb fitted, are they safe and legal?

The MoT is a minimum safety standard that does not permit dismantling to be carried out during the examination. Therefore, it is possible to have an unroadworthy car that has just passed its MoT Test.

Notably, the MoT Testing manual states:

Existing halogen headlamp units on vehicles... must not be converted to be used with high-intensity discharge (HID) or light emitting diode (LED) bulbs. If such a conversion has been done, you must fail the headlamp for light source and lamp not compatible.

This does not refer to complete replacement headlamp units which may be constructed with HID or LED light sources.

3. I fitted LED conversion bulbs to my car. Surely it's now safer than the old halogen bulb?

A lamp is not made safer just by being brighter. As halogen lamp optics are not designed to work with an LED bulb, some parts of the output pattern will be brighter and other parts will be dimmer.

The other issue involves light scatter, which can dazzle oncoming motorists. Regardless of these technical issues, however, it remains an offence to use LED conversion bulbs within an exterior lamp on the road for modern vehicles.

4. Are there any instances in which I can use an LED conversion bulb?

You can use an LED conversion bulb in an interior lamp, provided that the light emitted is not focussed on the road.

5. I wish to add LED lighting outside my car. How can I do this legally?

The only way is to use a complete lamp unit that has been tested and wears a Type Approval Mark from an approved manufacturer.

However, GEM has come across complete LED lamps that do not wear any form of Type Approval Mark and such kits admit in the very fine print on the packaging that they are not for road use. Buy with care.

Any modification, however, must be declared to your insurance company.

6. I drive a classic car and the headlights are very dim, compared to modern vehicles. Is there an exception for classic vehicles?

Since Brexit, the DVSA and the MoT permit LED conversion bulbs to be used in halogen exterior lamps but only on vehicles used on, or before, 1st April, 1986.

7. I have seen '501 LED bulb - road legal' and 'H7 LED Headlight bulb - Road legal UK' being advertised online - should I fit them?

We are aware of some sellers being keen to state that their wares are road legal, when they are not. While some bulb manufacturers insist that the legislation has not yet caught up with technology, the case remains (at the time of writing) that no road legal LED bulbs are on the market for modern vehicles.

Read our related blogs:

Lights - Driver intervention needed

Using your lights thoughtfully

Why you need to replace old HID headlight bulbs


Did you know? 

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