What do you use fog lights for?

Additional light focused on the pavement that gives you an extra edge, especially in near-zero visibility conditions (visibility so limited you have to stick your head out the driver's door window to see the center line). The fog lights also make it easier for you to be seen by oncoming traffic. Doesn't do much, but it is an extra margin of safety.

 

We have fog frequently (like the past three mornings), very heavy fog sometimes.

I have found my OEM fog lights to be moderately effective for me to see the road. I don't know whether they improve my visibility to other road users.

My OEM lights can be switched on independently (JDM model Prius) but I almost never use them that way in night-time fog (not enough illumination by themselves) -- although I will use them by themselves on a clear night so as not to disturb the stock and I will use them by themselves on foggy days.

 

Aussie fog lights on Prius (standard on all Prius) can be used with just parking lights on, which you will want on in fog so you have tail lights on.
try driving with parkers and fog lights next time you are in fog and see how it goes for you.

 

Yeah, same configuration here, but at night fog+parking lights don't throw quite far enough ahead for my taste. The fogs do throw more illumination down on the road surface though which I do appreciate.

 

I use 'em just because they look cool. B)

 

<div class='quotetop'>QUOTE(banjoman @ Oct 30 2007, 01:10 AM) [snapback]532306[/snapback]</div>

Proper fog lights are actually snow and fog lights. often when its foggy the fog floats a little way off the ground. If you can get a light under it you light up the road more and the fog less. When you shine a normal headlight on fog or snow you get a tunnel effect where half of all you can see is glowing white dots or a glowing misty cloud. The road is obscured behind it somewhere and the eye tires quickly.

I don't have the stock Pri fogs (next car maybe) so I don't know if they're real or decorative. I never had any trouble seeing people coming if they have lights on. It makes the fog glow.

 

<div class='quotetop'>QUOTE(efusco @ Oct 30 2007, 06:16 AM) [snapback]532311[/snapback]</div>

I'm intrigued by this statement. Is this because they can't be turned on without the headlamps in the U.S.? I've never been quite clear why that is - what do FMVSS regulations say about front fog lamps?

In the rest of the world, they can be turned on without the headlamps, and are definitely front fog lamps as defined by UNECE R48. (And the US version would not meet those regulations, as they can't be turned on independently).

As for performance - they do exactly what front fog lamps are supposed to do - illuminate the road edges and markings enough for you to be able to make safe progress at low speed in extreme fog or snow conditions. But not being able to turn the headlamps off defeats the object for the U.S. model.

My only real gripe about them is that you can't turn on the rear fog lamps without turning on the front fog lamps. Seems rather batty to me - you need the rear fog lamps much more frequently than the front ones.

 

For what it's worth, here's a summary of the UNECE rules for foglamps (from R48 and R19):

• Colour: white or selective yellow
• Number: 2
• Position: Not more than 40cm from the edge of the vehicle, between 25cm and 80cm from the ground
• Visibility: 5° up and down, 45° outwards, 10° inwards
• Direction: forwards, not varying with steering
• Connections: Must only come on when position lamps are on. Must be possible to switch on and off independently of main beam and dipped beam
• Dashboard tell-tale: Mandatory
• Beam shape: Basically left-right symmetrical with a horizontal cut-off aimed 1.1° downwards. Most light required 1.7-3.4° downwards, 10° left and right - significant light also required at the same inclination 20° left and right.

I'd be interested to know how the US' FMVSS rules differ, particularly on the connections.

 

<div class='quotetop'>QUOTE(DGH @ Oct 29 2007, 10:27 PM) [snapback]532318[/snapback]</div>

wow... and why exactly oes that make us RUDE and MORONS for leaving them on?

<div class='quotetop'>QUOTE(Mr. Zorg @ Oct 30 2007, 05:38 PM) [snapback]532669[/snapback]</div>

ditto.... me, too! (guess that makes us rude, obnoxious and oblivious)

 

<div class='quotetop'>QUOTE(DGH @ Oct 30 2007, 02:07 PM) [snapback]532577[/snapback]</div>

*rolls eyes*