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Recommended Posts

Posted

I have a 2002 911 Carrera Cabriolet (C2) and when I was leaving Texas Roadhouse after dinner last week, one of my friends noticed the right rear fog lamp was not illuminated. All of the front and rear lights work, but when I pull and turn the lights onto the fog light position, the rear right fog light does not work. The left rear fog light works fine. A European repair shop told me that the American cars were made with the left rear fog light working, but not the right rear fog light. DOES ANYONE KNOW IF THIS IS CORRECT?

Posted

That is correct. My 2000 only has the left rear fog light come on. There are some posts here that tell you how you can wire up the other fog light if you want them both to work.

Posted

It is correct. Our Volvo and our past Saabs did the same thing, so it isn't just a German thing...

I think the Cayenne is the same way, but I haven't checked...

Posted

Think about it, two working rear fog lights would be called "brake lights". If they both light (as rear fog lights), how would the person behind you know when you were braking?

The repair shop is correct.

Posted (edited)

The logic behind this is that the one light is not a fog light for you to see but instead, during inclement weather, a light so others behind you can see you better. One light can easily pierce through the weather without blinding those followers when two are on. Just leave it the way it is.

On an interesting note, I had a cop pull me over once and he wrote me a ticket for one of my lights being out. As he gave me the ticket, I asked which light was out so I could get it repaired. As I exited the cabin, I flipped it off. lol. He was a little dumb founded when my brake lights came on and off with no problem. A little fun at his expense. :)

Edited by my996
Posted

Dennis you got the joke. Seriously I swear by the rear fog light. My 83 Euro SC originally came with it but it had been disconnected at some point and the light removed. I reconnected it and in the fog & rain it is a lifesaver. Both the Boxster S and My Land Rover Discovery have it. American cars need to get with it. Also on European cars the fogs only work in low beams, not on highs or by themselves. I don't think American cars are like that, but I could be wrong.

Posted
I wired up the right rear fog light on my 996.

rearfogsweb.jpg

Orient Express-Next time I'm in South City, I'll make sure to pay you a visit :D How long did it take to do the wiring and how much did it cost?

Posted

I disconnected the "fog" wire and wired both of the "extra" rear lights into the brake circuit. Goal was to have a much more pronounced indication of brake application. I also wired my DRL circuit into the street/parking/tail/marker light circuit as is done in Canada for DRLs.

Posted

I believe the logic behind having only one rear foglamp (some Opel/Vauxhall manuals refer to it, I think properly, as a "fog tail lamp"), is that in fog or very bad weather, the driver behind can tell the driver's side of the car he's following.

From what I can remember, from a BMW 5-series manual in the '80s (English language, general export), in the Federal Republic of Germany, the rear foglamp is only to be used when visibility ahead falls below 50 metres (164 ft/55 yards) to reduce glare to the driver behind, and front foglamps if visibility falls below 100 metres (328 ft/110 yds). For the rear foglamps, that's about 10-11 car-lengths.

Also, from the manual, as the 5-series ROW cars had 7-inch outer (high/low beam) headlamps and 5-inch inner (high beam/driving) headlamps, the front foglamps are wired only to operate with the low-beam outer lamps. The manual said that in Germany, only four headlamps are allowed on at the same time, hence the wiring. (But it didn't say it was because high beams are useless in fog)

Posted (edited)
I believe the logic behind having only one rear foglamp (some Opel/Vauxhall manuals refer to it, I think properly, as a "fog tail lamp"), is that in fog or very bad weather, the driver behind can tell the driver's side of the car he's following.

From what I can remember, from a BMW 5-series manual in the '80s (English language, general export), in the Federal Republic of Germany, the rear foglamp is only to be used when visibility ahead falls below 50 metres (164 ft/55 yards) to reduce glare to the driver behind, and front foglamps if visibility falls below 100 metres (328 ft/110 yds). For the rear foglamps, that's about 10-11 car-lengths.

Also, from the manual, as the 5-series ROW cars had 7-inch outer (high/low beam) headlamps and 5-inch inner (high beam/driving) headlamps, the front foglamps are wired only to operate with the low-beam outer lamps. The manual said that in Germany, only four headlamps are allowed on at the same time, hence the wiring. (But it didn't say it was because high beams are useless in fog)

As a point of FACT fog lights when used in conjunction with low beams are actually a DETRIMENT to your night time distance vision.

Fog lights should ONLY be used alone in day time conditions that warrant their use.

Drivers who have fog lights on along with either high or low headlights are doing that only for BLING...!!

Most states REQUIRE the use of your main headlight beams between the hours 30 minutes after sunset until 30 minutes prior to sunrise.

Edited by wwest
Removed flaming remark
Posted
As a point of FACT fog lights when used in conjunction with low beams are actually a DETRIMENT to your night time distance vision.

Fog lights should ONLY be used alone in day time conditions that warrant their use.

Drivers who have fog lights on along with either high or low headlights are doing that only for BLING...!!

Most states REQUIRE the use of your main headlight beams between the hours 30 minutes after sunset until 30 minutes prior to sunrise.

wwest, instead of spouting "FACTS" in CAPITAL LETTERS, it would be good education for other people (and yourself) to have some references and research to back up your OPINIONS, before you start confusing people.

http://lmgtfy.com/?q=how+do+fog+lights+work%3F

Most articles say that some people find fog lights helpful and some do not, so don't take any one person's opinion as gold. Real fog lights project light forward and down onto the road, but they have a horizontal cut off at the top that prevents light from pointing up. It is very important that they be aimed correctly so that light does not point up! Some cars come with "driving lights" that don't have as much of a horizontal cut off so they might aim light upwards, which won't help in fog.

The idea is that fog lights help prevent glare from blinding you because the light does not bounce off the fog and directly back in your face. This is because they are mounted low and aimed low. High beams don't work in fog because more light is aimed up higher than low beams, so there is a lot of glare from light bouncing off the fog particles and back in your face. Visibility has a lot to do with the angle of reflected light off the fog.

Some say fog lights are located low to "cut under" the fog as well, since some fog sits above the road a foot or two. Again, these are mostly opinions from other people's experiences, your experience will differ depending on your car, type of fog lights, their aiming, and the type of fog you drive in. There is no universal rule of thumb.

  • Upvote 1
Posted (edited)

Must also disagree with wwest's assertion.

The low mounting position of a fog lamp helps it do its job. But fog lights are also lensed differently and, more recently, often even use different light sources. In my Rangie, for example, the xenons are hopeless in fog, but the fog lamps are halogens and they help immensely. Likewise in snow. And especially at night. Front fog lamps are for seeing, not for being seen.

Regarding the original topic of this thread, personally I would never wire up a second fog lamp in my 996, specifically because of the risk of confusion with brake lights. With my Rovers, on the other hand, the rear fogs are in their own housings in the bumper. There's no risk of confusing them with brake lights and thus there are two. Just my .02.

Edited by BruceP
Posted
Regarding the original topic of this thread, personally I would never wire up a second fog lamp in my 996, specifically because of the risk of confusion with brake lights.

+1

  • 2 months later...
Posted (edited)

Someone mentioned snow...

Never use fog lamps in snow - all you do is light up the all the flakes as they hit the front of your car. I've had to drive in heavy snow and the best solution (other then pulling over) was turning my head lamps off and running with the lower watt DRL's and I found that I could see much further down the road. Many places in northern Canada - there is no where to pull over (all sloping gravel into deep ditches) or there is a great risk of being hit from behind if you do stop.

*Less* lighting is actually better in extreme conditions as your eyes adjust to the distance and your brain seems to ignore the thousands of flakes hitting the windshield - more so when the frontal area isn't lit up like it was a rock concert. I always shake my head when I see someone with high beams on or fog lamps on in heavy snow. Fog lamps for fog only and on 996's - the fog lamps are still mounted too high to really be of any good. If you want better protection in really bad weather, turn on your 4 ways. If you have to consider the 4 ways then you really should be finding a safe place to park if you have that option anyway.

Half the time up here we just follow the blue flashing lights (snowplows) anyway and the last guy in line uses his 4 ways until the next hanger on joins the line and then he turns his 4 ways on! (This is only one reason why I store my 996 for the winter! :) )

Edited by torontoworker
  • Moderators
Posted
How long did it take to do the wiring and how much did it cost?

It took me about an hour to wire it in and it cost a 4 ft piece of wire and a crimp connector.

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