Legaility of retrofitting LED headlight bulbs to our cars - change in MoT rules

[gordon higginbotham]

There has been a change in the MoT regulations recently, l from February 2021, that made converting a halogen headlamp to LED a MoT fail as had been the case with fitting HID bulbs for years. Our cars never had Halogen filled bulbs (they were tungsten filament either vacuum or filled with an inert gas such as Argon).
The vehicle lighting regulations are dated 1989 so our older vehicles are still exempt from needing bulbs with EU approval so the law has not changed - just the MoT regulations which seems inconsistent.
Converting original headlamps to LED bulbs, provided the beam pattern is correct, properly aimed and therefore not dazzling, are ok. Beware of cheap Chinese sourced LED headlight bulbs as they can have very poor beam shape outside MoT requirements.
I came across the following letter from the Department of Transport, which somebody had posted on facebook, and assume is genuine. This seems to resolve the position satisfactorily.

[jameswheildon]

Good work, Gordon. So we can fit LED headlamp bulbs legally, but they must be adjusted so that they do not dazzle. It is worth persevering then, but I need persuading that they can be made to give a useful beam pattern when fitted to our headlamps.

[gordon higginbotham]

James,
I think you are quite correct in needing to be persuaded that a good beam can be obtained. I am in the midst of going through this at the moment. I have a 3 part strategy!
1. Fit bulbs into refelectors and check that I have a focussed beam that dips. Achieved. Then get them checked at my friendly MoT garage and see if they meet requirements. Awaiting annual "MoT inspection".
2. If not getting satisfactory beam spread try some borrowed Model A lenses which are flat and I think could replace existing frosted plane glass and check beam shape.
3. If still not OK replace reflectors as last gasp effort!!
I have been held up by the lockdown at the moment but will report success or failure later!

[jameswheildon]

Hi Gordon,

I'll await your further report with interest. I have never been satisfied with the headlights on any of the Talbots that I have owned. The best compromise that I achieved some years ago was to set up the original lamps with twin dipped bulbs showing the edge of the road quite close to the car, which resulted in the main beam being set too short, but at least it did not dazzle, but then I had a pair of modern (35 years ago!) driving lamps which I set to work only on main beam but with the ability to switch off. The downside was the drain on the battery.

[gordon higginbotham]

James,
The main problem is that the Rotax 590 parabolic reflectors are not designed for a modern twin axial filament with a Graves mask to get them both in focus. The LED units I selected were H4 type but with a removable mounting plate that allowed them to be fitted into the standard ba15 tube so could be moved axially and clamped in position allowing focus to be adjusted. Attached are the beams produced without the front lens. What is needed is a front glass that is ribbed to spread the beam horizontally. The Model A Ford of 1928 has a simple ribbed design and is 8.5" diameter so could be trimmed to fit if it does the job.

[gordon higginbotham]

James,
The following change now confirms the position - my take is we can use LED headlight bulbs provided they don't dazzle and are correctly aimed.

Special Notice 01-2021Headlamp conversions
Published 19 March 2021

1. About headlamp conversions
Section 4.1.4 of the current MOT inspection manuals for both motorcycles and cars and passenger vehicles, states 'Existing halogen headlamp units should 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.'
2. Changes to current rules
From 22 March 2021 we're changing these rules so that not all motorcycles and vehicles will fail the MOT test if their halogen headlamp units have been converted to be used with HID or LED bulbs.
Class 1 and 2 motorcycles
Class 1 and 2 motorcycles must not be failed for the defect 'Light source and lamp not compatible'.
Headlamps must comply with all other requirements of the test and headlamp aim.
The motorcycle inspection manual will be updated shortly, and the ability to select the defect within the MOT testing service will be removed.
Class 3,4,5 and 7 vehicles
For class 3,4,5 and 7 vehicles, the defect 'Light source and lamp not compatible' only applies to vehicles first used on or after 1 April 1986.
Should a vehicle be presented for MOT test with conversions before 1 April 1986 they must not be failed with immediate effect.
Vehicles presented with converted halogen headlamp units first used on or after 1 April 1986 will continue to be failed.
Headlamps must comply with all other requirements of the test and headlamp aim.
The cars and passenger vehicles inspection manual will be updated shortly.

[jameswheildon]

Hi Gordon, On the very day we are discussing LED headlamps the law is changed to our advantage. Some 35 or so years ago, I was frustrated with my 95's headlamps lack of light. I had noticed that Foden lorries had 12" Lucas headlamps and I acquired a pair. I cut down the reflector and had the glasses ground to fit our Rotax rims. They wern't a huge success, but I might try again using LED bulbs, the lenses were ribbed.

[gordon higginbotham]

Hi James,
Please find attached some information on LED bulbs you might find interesting. They allow easy adjustment for right or left hand driving as the H4 mount is c lamped by a screw and can be easily removed in total as the heatsink easily unscrews so this gives much scope for fitting. There is no doubt that the best arrangement would be to select a good lamp reflector and lens designed for double dipping and possibly install behind a stippled front glass?
The link to the website is: https://www.classiccarleds.co.uk/col...lection?page=2

[jameswheildon]

Thanks Gordon, I'll follow that up.