The legal situation is that lights are required to be ADR compliant (assuming we are talking about vehicles made since the ADRs existed). When a vehicle is introduced to the market, lights must be shown to be compliant. Changing from an incandescent bulb to an LED means that even if the light does still meet the requirements, it is no longer the same as the one that did, and at the very least would need engineering approval. Complete LED lights marked ADR compliant and sold as a unit have gone through the approval process and could be used as a replacement light - not the same situation.
As far as HID lights go there are two problems. The first is that as I understand the situation, HID lights are required to be equipped with washers and wipers and provision for height adjustment from the driver's seat. The second is that the arc in the HID is a different shape to the incandescent filament, owing to inescapable laws of physics. This means that a lens or reflector designed for one cannot give the same beam spread shape for both types of lamp, and again, we get into the same legal situation as with the LEDs, except that in this case the conversion is very obvious to other drivers. See Daniel Stern Lighting Consultancy and Supply for a full discussion.
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
Bookmarks