DRL - quick question

[ianedwards]

Quick question,

Can daytime running tights be a substitute for side lights,

I.e - if I built some DRL's into a front bumper would I also need side lights, ??

If so, there is no point, ??


Cheers

[Anton]

I'm fairly sure you can't substitute a pair of tights (running ones or otherwise) for the lights on your vehicle.

Daytime running lights have to be bright enough to be seen during the daytime, so they're illegal to have on at night (because they can cause dazzle). So no, you can't have them instead of sidelights - in fact, current EU law states that running lights *MUST* automatically switch off if you put the sidelights or headlights on.

Have a read here.

[Ladaman]

I was just about to say you were wrong Anton, as my daily car has LED daytime lights, that do stay on with the headlights, BUT this paragraph must apply,

Daytime running lights don't have to be separate lights - some car manufacturers combine them with the front position lamps (side lights) in which case the daytime running lights will dim when the headlights are turned on.

Even though I've never noticed that they dim. Then again, I'm inside it not looking at them

[ianedwards]

Tidy. good job I asked before I wasted a few quid. Get headlights with a side light then.

Right so, if I built some small round fog light lights into a bumper with those angel eye things round them, would the ring have to go off at night when the head lights come on, not sure if they are treated as drl's

[Anton]

I was just about to say you were wrong Anton, as my daily car has LED daytime lights, that do stay on with the headlights, BUT this paragraph must apply,

Daytime running lights don't have to be separate lights - some car manufacturers combine them with the front position lamps (side lights) in which case the daytime running lights will dim when the headlights are turned on.

Even though I've never noticed that they dim. Then again, I'm inside it not looking at them

This is an EU law, but I think it's applied selectively across europe - different EU countries have different laws. Some require driving lights only for non-urban driving, for example. So just because the EU says this is "law" it doesn't mean that manufacturers are applying those laws to UK cars in the way that document suggests.

So all I can suggest is that "dimmable" driving lights that go from 25watt (or equivalent LED power) to 5watt should be legal as a sidelights/daytime driving light combo. That might be what you have.

If it's made with a set of LED's, it should be fairly trivial to switch them all on with ignition live, but have 4 out of 5 go dark when you switch to sidelights/headlights. Just wire them into ignition live via a fuse, then have 1 out of 5 grounded locally. Then have the other 4 grounded via a relay that is controlled by the output of the lights - that is to say, a normally open relay if he has positive switched headlights, a normally closed relay if he has negative switched like mine.

So in my SJ, the relay would be closed until the control side of the relay was grounded (by switching on the sidelights) when they'd go out.

In a positive switched, you'd just wire it up the same, but with a normally open relay.

Or am I missing something?

[Anton]

Tidy. good job I asked before I wasted a few quid. Get headlights with a side light then.

Depends - were these daytime running lights "dippable"? Could you illuminate them to 20% as well as full power? Because if so, they might be fine.

Right so, if I built some small round fog light lights into a bumper with those angel eye things round them, would the ring have to go off at night when the head lights come on, not sure if they are treated as drl's

If the "angel eyes" put out 5W of light (based on normal bulbs, not LEDs, which output a LOT more for the same wattage) then they can be permanently illuminated. You can't have more than 5W coming out of your lights when the sidelights are on. I don't, however, know if that's in total or combined.

[turbo-tom]

Disco has got angel eyes in the light bar, when driving with them on the police never seamed that bothered about them.

[donkeychomp]

If you want driving lights get a Volvo...