20 years car development - huge leaps and small backward steps

[DanceswithUnix]

I could be wrong, but I did some research into legitimate conversions and for the most part I don't think there's really a way to do it besides replacing the whole headlamp assembly for another approved one. Given how precisely they're designed to get the filament in the focal point of the reflector, a different type of light source would likely throw it way off and ruin the light pattern like you say.

Regardless of whether it would pass a pattern test, what I also concluded is that you'll effectively void the E mark by installing any non-standard lamps; even if the lamps you install happen to come with their own E mark (as some sellers claim, implying they're 'legal'), the assembly as a whole will not be compliant as they were not designed to be used together - headlamps are rated as a whole, not as a sum of parts.

I've also just found this, apparently the DVSA has removed some of the ambiguity and outright said it's not permitted to convert halogen units: https://greyhead.co.uk/other-things/...ights-legal-uk

Absolutely, but you can get halogen bulbs that are still halogen so perfectly legal but 50% brighter. The key is that being halogen the filament is the same shape and in the same location as a cheap filament so the light pattern is correct, it's just more efficient so gives more light.

[watercooled]

It's just the HID conversions I was talking about. WRT the brighter bulbs, I was considering them a while ago but there's not much in the way of performance tests available; I found some by ADAC if I remember correctly, but subjective reviews ranged from no improvement and short life, to a massive improvement.

[badass]

HID conversions are illegal. By law cars with HID lamps must be selfl evelling and the kit to do so is on the suspension. Doubt any of the aftermarket kits can do that.

[watercooled]

According to the government, that's not strictly true, they acknowledge that vehicles may be fitted with such systems (and washers) and if so they must work.

Vehicles with high intensity discharge (HID) or LED dipped beam headlamps may be fitted with a
suspension or headlamp self-levelling system. If these systems have been fitted, they must work.

You can't convert an existing unit, but replacing one isn't explicitly forbidden from what I can see (nor would that make sense as they're effectively interchangeable OEM parts in some vehicles).

Existing halogen headlamp units shouldn’t be converted to be used with HID bulbs. If such a conversion
has been done, you must fail the headlamp.

The wording is fairly clear - existing halogen units can't be converted. Kits are basically a no-go then.

[kalniel]

It's just the HID conversions I was talking about. WRT the brighter bulbs, I was considering them a while ago but there's not much in the way of performance tests available; I found some by ADAC if I remember correctly, but subjective reviews ranged from no improvement and short life, to a massive improvement.

http://www.autoexpress.co.uk/accesso...018-group-test

It's AE though, so take with a little bit of sodium..

[badass]

According to the government, that's not strictly true, they acknowledge that vehicles may be fitted with such systems (and washers) and if so they must work.



You can't convert an existing unit, but replacing one isn't explicitly forbidden from what I can see (nor would that make sense as they're effectively interchangeable OEM parts in some vehicles).



The wording is fairly clear - existing halogen units can't be converted. Kits are basically a no-go then.

I'm confused by the semantics of the first 2 lines - I've read it 5 times and gone cross eyed. However the final sentence is clear. HID conversions are illegal. Any car that cannot pass its MOT at any point in time is technically illegal to be used on the road as a rule of thumb - although it's extremely rarely enforced.

Another rule of thumb I have heard (used by police) is that if it is on the vehicle, it should be working. e.g. rear wipers are not required, however if your car has one, it must be working.

[watercooled]

It reads very clearly to me, something like this: Some vehicles are equipped with HID or headlamps. Of these vehicles, some are fitted with self-levelling systems - if so, these systems must work.

There is, as far as I can tell, no explicit requirement for such systems on a vehicle equipped with HID/LED headlamps, merely that any fitted systems must function correctly.

FWIW, some (if not most) of the self-levelling mechanisms are integral to the headlamp assembly and don't require self-levelling suspension, so it's not like the entire car needs to be designed for it.

But yeah, modifying a halogen unit to work with HIDs is not permitted according to that (draft) document. LEDs are notably omitted from that phrase, interestingly!

@kalniel: I think I encountered that article or one similar to it when I was researching (it's originally dated back in 2017), but it's patronisingly stripped of any objective data to examine for ourselves. If they took the time to make measurements, why are they keeping results mostly to themselves and expecting us to trust their subjective conclusions? /rant

Or am I just missing a link to a table or something?

[DanceswithUnix]

FWIW, some (if not most) of the self-levelling mechanisms are integral to the headlamp assembly and don't require self-levelling suspension, so it's not like the entire car needs to be designed for it.

How does that work? It can't work using gravity as a reference else if you go down hill the lamps would point upwards relative to the road and into the faces of oncoming traffic. It has to be in reference to the angle of the car relative to the road, easiest picked up on rear suspension height.

I assumed these days they would use the normal electric manual suspension levelling system (standard on my shopping trolly, so I presume cheap enough) coupled with a sensor at the back and a few lines of code to move the lights if the sensor registers a change.

There is, as far as I can tell, no explicit requirement for such systems on a vehicle equipped with HID/LED headlamps, merely that any fitted systems must function correctly.

I think that is like seatbelts. If you don't have rear seatbelts then that's fine and an MOT pass, but any car made after something like 1976 must have rear seatbelts to pass type approval and be classed as a car so it can get a registration number.

There was a rather good web page out there that showed the difference in halogen and HID light source shapes and hence how putting the wrong bulb into a reflector gave you a light pattern it was never designed to produce.

[watercooled]

Moving in to stuff I'm not 100% about but I'll do my best (and I'm interested so I'll do more research later). Also typing on phone so forgive short(er) sentences.

Light assemblies have an upper limit to stop pointing upwards when going downhill.

Cars can have a plethora of sensors e.g. suspension height regardless of headlamps installed at the factory (they're often interchangeable) and said sensors are accessible via the CAN bus. They don't have to be integral to the headlamp. The adjustment can be motorised in the assembly though.

I actually mentioned seatbelts (and airbags) as an example in an earlier point but removed it to avoid confusion in making my point as they became mandatory in cars produced after a date. I don't think that's the case here.

I'd be interested in that conversation test if you know where it was! Be a good way of demonstrating the issue to people too.

[DanceswithUnix]

Cars can have a plethora of sensors e.g. suspension height regardless of headlamps installed at the factory (they're often interchangeable) and said sensors are accessible via the CAN bus. They don't have to be integral to the headlamp. The adjustment can be motorised in the assembly though.

That is basically what I was saying, My current car has adjustable headlamps, the addition of a suspension height/load sensor could make it automatic.

I am quite certain though that self levelling is a current requirement for HID lights in new cars.

Edit: Some googling found this, UK law doesn't mention HID lamps making them illegal under UK law but EU law overrides that so they are covered under ECE 98 for type approval and the UK lets aftermarket parts slide as long as they also get over that bar which includes washers and self levelling:

https://www.gov.uk/government/public...-hid-headlamps

[watercooled]

Ah I see what you mean. Also good find with that gov article, makes things quite clear.

[peterb]

That is basically what I was saying, My current car has adjustable headlamps, the addition of a suspension height/load sensor could make it automatic.

I am quite certain though that self levelling is a current requirement for HID lights in new cars.

Edit: Some googling found this, UK law doesn't mention HID lamps making them illegal under UK law but EU law overrides that so they are covered under ECE 98 for type approval and the UK lets aftermarket parts slide as long as they also get over that bar which includes washers and self levelling:

https://www.gov.uk/government/public...-hid-headlamps

I looked at fitting aftermarket HID, but that was definitely iffy, so I then looked at getting the proper Mfr HID units for the car (it was a factory fitted option when new). But the FF option included self levelling suspension - so unless that was fitted as well, the HID would still be illegal and likely to result in an MoT fail.

I think I started a tread about it on HEXUS.

Edit - I did https://forums.hexus.net/automotive/...onversion.html

[watercooled]

I had a look at the price of the OEM hid units for mine and they're about £500 each...

[Butcher]

I had a look at the price of the OEM hid units for mine and they're about £500 each...

Bargain. I broke both my front HID headlights. £900+VAT each for oem replacements was quoted. I got aftermarket shells for £500 a pair and reused the OEM electronics.
They self level; the sensor is attached to the rear suspension control arm, so it levels based on how much stuff you have in the boot.

[Lowe]

They self level; the sensor is attached to the rear suspension control arm, so it levels based on how much stuff you have in the boot.

Which is great until you lower the car...

What the actual did you do to your headlights?

[Butcher]

Which is great until you lower the car...

What the actual did you do to your headlights?

Indeed, which is why mine has an adjustable linkage, so it can be corrected for lowering.

I crashed the front of the car into an armco at Snetterton race track.

Like so: