Low beam and fog HID together?

So you know it is illegal, and will annoy others so bad you plan to be ticketed, and you want our advice? Mine is "Buy some other car, Prius owners are getting enough bad press."

 

I thought High Beams + Fog Lights were illegal in Ca. Not Low Beams + Fogs. Is this correct or are HIDS a special case?
Jim

 

No 2010 in the US is sold with HIDs, just halogens and LEDs. Since it is not legal to convert between types according to the NHSTA, a 2010 with HIDs has to be illegal, high beam or low beam. (It is not legal to make a bulb that plugs into a socket not intended for that type bulb)

My 2009 Prius was purchased with HIDs and fog lights. You can only run the fogs with low beams, stock.

 

On all US cars, you are supposed to only run the fog lights with your low beams, and not with your high beams. That's why on all cars that have factory fog lights on them in the US, they turn off when you turn on your high beams. You can modify this so the fog lights stay on with the high beams (euro-spec) by hard wiring it, or possibly via the software with something like a ScanGaugeII.

 

Thats why I love texas. HID lows, highs and fogs. no one cares.

 

First of all, the headlights are projectors so there is a much better cutoff for the light compared to a conventional halogen setup. Blinding oncoming traffic is going to be much more difficult because of the cutoff. Second, HID's have a very low amperage pull as they use a ballast to up the voltage to light the bulb. Much more light with less wattage equals better efficiency. Last but not least, foglights are meant to run with low beam headlights. High beams are usually the no-no. I personally think you and others are being to much of a worry wart when it comes to this. I have 6000k HID's in place for my fogs and just adjusted them properly. They reflector is for more of a wide beam as opposed to straight line so as long as they are adjusted properly you shouldn't have any problems. I'd just do it. Just what ever you do, if you decide to tint your tail lights don't ask for opinions here. Causes way too many problems. Wasn't me, but I've seen it happen.

 

Sorry Tideland, but I have to disagree. Besides I would say 85% of the cars that have factory fog lights don't allow the fogs to be on without the headlights. You still need to see straight ahead which is what the low beams offer. The fogs are a wide beam to light the sides of the road to see markers and the like so you are sure to stay in your lane. Not to mention that is another reason why true fog lights are yellow in color. The color reflects better which means you can see it better in foggy situations. White lights are typically just a driving light just to help light up the road directly in front of the car.

 

I just noticed this with the Prius the other night when I changed out the fog light bulbs. At least on my BMW you can run the fog lights with the parking lights and no headlights. There's a mod out there that works on most cars, and it was the same for my 2006 Audi, where you can to hardwire the fog light signal wire to the headlight wire (very easy mod, just snip & tap 1 wire). I assume it's the same way on the Prius... 3 wire switch, only the wires are on the column and not a separate fog light switch off to the side (which made the Audi mod much easier). Just look for the parking lights power/signal wire with a multi-meter and find the fog light signal wire. Cut the fog light signal wire and tap into the parking light power/signal wire, so the fog lights will work when the parking lights are on (since it will see the signal). Putting it back is as simple as removing the circuit node (tap) and connecting it back to the cut wire.

That'll be my next weekend project. I just need to figure out if I can access everything from under the dash/steering column, or if I need to remove the steering wheel to get to the headlight stalk.

 

I am afraid I disagree with the above comment about the purpose of fog lights being to light up the margins of the road. The difference in fog lights is the angle of the light relative to the roadway and the resulting reduction in "bounceback" of light from the fog, as is experienced with low beams (and even more so with high beams). This is why fog lights are mounted so low on the front of the car.
The result is that, while they light the road less well, true foglights do not produce that glaring light reflection that makes driving at night in the fog so difficult. If they can only operate when the low beams are on, as on my 2005 prius, the benefit of foglights is defeated. To me it is poor engineering. Perhaps if the toyota engineers woudl drive a mercedes for a spell they might catch on to this.
To experience the benefit of true fog lights, the next time you are alone on a road at night in heavy fog, or in a blinding snowstorm, IN A CAR THAT UNLIKE THE PRIUS HAS BRIGHT PARKING LIGHTS, try momentarily operating on just the parking lights instead of the headlights, and you will notice that, paradoxically, you can see much better and expereince much less glare/bounceback. If you can see any other traffic, DO NOT ATTEMPT THIS.
What is needed is a mod that allows for driving (at slower speeds, as is always called for in poor visiability conditions) with only the fogs and parking lights but no headlights. If anyone knows of such a mod please let me know (I cannot quite seem to find it by searching this forum, but I know it's out there somewhere). Thanks all.