Thought it would be a good idea to give TM some info on upgrading headlamps and the MOT ( in the UK) as things have just changed a bit.

The upgrading of existing halogen headlamps with HID bulbs has been a MOT fail for a few years now. However upgrading with LED bulbs was OK. Not anymore! From 11/01/2021 the MOT rules have been updated to make the fitment of LED bulbs ( in existing halogen units) a fail.

I attach the new rule for clarity.

4. Lamps, reflectors and electrical equipment

4.1.4 Headlamps - Compliance with requirements - Changed sentence from 'Existing halogen headlamp units should not be converted to be used with HID bulbs. If such a conversion has been done, you must fail the headlamp.' to '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.'

That's useful to know. I imagine many MOTers will turn a blind eye (I've know several people who get away with HID conversions) but forewarned is forearmed.

I'm more than happy with my Halogens but thanks for the notice as a lot on here have upgraded and will be affected by the changes.

Presumably that means those of us who have already changed to LED bulbs would have to change back to Halogen or risk MOT failure.

Or did I misunderstand.

Is it only a problem during the MOT investigation or can you also get problems during a police check?

How is the MOT tester or police officer to know for sure what bulbs are in the headlights?

I understood that they were not permitted to dissamble any part of your car, or am I wrong?

it is very easy to tell the difference just with a visual inspection though the lens.

The Police officer won't be bothered I'm sure. The MOT tester won't be disassembling but if he looks, will be able to spot a LED bulb i expect - the light they give off is a big giveaway!
Of course LED sealed beam headlamps are now being sold ( by Wolf performance for example) and these are fully legal at MOT and look traditional opposed to the PlusFour style items.

How will the tester spot if you have a nice pair of original looking, but modern LED sealed beam headlamps from Wolf?, or your originals with LED bulbs installed? Not sure - but in any doubt us testers are told to give the benefit of any doubt to the presenter......

Many thanks for update Andy although not surprised given HID headlamps pre dated LED'S. You couldn't maintain regulations for one technology then ignore another newer one with the same potential.

What of the self levelling and headlamp cleaning requirements though for LED's as already established for HID units or is this something that is not checked during MOT's?

This is probably a dim question (particulary if you still have halogen lights) - why practically are LEDs/HIDs a bad thing, ie a MOT fail? I would have thought they would actually be.a safety feature - my MG Midget and 4/4 both of late 1960 era light up the road in a much less satisfactory way than my modern SEAT Leon with LED headlamps.