85mm

I was just following my wife in her gl450 on the way to taking the civic to the dealer. I had the front and rear fog lamps on before we swapped cars. It looked like the right rear fog lamp was out but there was no fault warning in the dash. I opened up the rear panel to inspect the bulb. Nothing looked easily accessible but I did find a subwoofer. I read the manual. The manual reads something like, 'rear fog lamp driver side only'. Why would they do this? It makes it look like I'm not maintaining my car properly.

vinceching

thats the way it is supposed to work. only on one side so drivers know it is the rear fog light.

you can install another bulb and it will work. but then you will run into the problem of people in the rear thinking you are braking.

Nevada Jack

This is a EU requirement I think and has been standard procedure on MB's for as long as I can remember.

06c230hwd

Lol!? It doesn't make you look like you don't maintain your MB. It looks like you are a MB noob! Haha, j/k! I pulled my headlight switch out constantly for the first month I owned it always expecting a difference in wattage in my front foglights or something, but never got any results. One night by accident I turned it on in my driveway with the garage closed and I was able to see the bright lights reflection... boy did I feel silly :P

If you ever wake up to 5 feet of visibilty in early morning fog at least you have the comfort of knowing it is easier for other drivers to see you... besides that, I wouldn't turn it on.. unless of course you plan on entering the skies!

AsianML

It's easier for the driver's behind to know where the driver's side is and to distinguish tail lights from brake lights.

N'AWLINS

Been an M-B safety feature for about 30 years....one red light, driver's side.

85mm

Thanks guys. I still think it's an odd feature now that the rear window brake light distinguishes braking red lights from other red lights. My Discovery had two factory rear fog lights (probably because rover had too many complaints from people thinking it was really an electrical glitch! lol). I actually don't like using the rear fog lights now. I have this thing about keeping my cars well maintained. I love seeing 10 year old cars looking good as new. I had a 10yr old Range Rover which had assorted minor issues but I atleast kept it cleaned and replaced any bulbs that blew out.

ksdprasad

did anyone tried installing the passenger side bulb in rear fog light.

MKW

My German cars have had one rear fog light for decades - I like that essential safety feature and use it in inclement weather whenever I can barely see the car in front of me - which means the trailing car can't see ME !. I would avoid double rear fogs - it annoys uninformed drivers who think you are senile and driving with foot on brake pedal or results in inattentive drivers not noticing your brake lights should you use them suddenly.

slim nicky

From Wikipedia: http://en.wikipedia.org/wiki/Automot...Rear_fog_lamps

All my cars - Audi, VW and MB have had only one rear driver's side fog light .

Rear fog lamps
(ECE Regulation 38, SAE J1319) In Europe and other countries adhering to ECE Regulation 48, vehicles must be equipped with one or two bright red "rear fog lamps" (or "fog taillamps"), which are switched on manually by the driver in conditions of poor visibility to enhance vehicle conspicuity from the rear. The allowable range of intensity for a rear fog lamp is 150 to 300 candelas, which is within the range of a U.S. brake lamp. For this reason, many European vehicles imported to the United States have their rear fog lamps wired as brake lamps, since their European-specification brake lamps may not be sufficiently intense to comply with U.S. regulations, and rear fog lamps are not required equipment in the U.S.

Most jurisdictions permit rear fog lamps to be installed either singly or in pairs. If a single rear fog is fitted, most jurisdictions require it to be located at or to the driver's side of the vehicle's centreline — whichever side is the prevailing driver's side in the country in which the vehicle is registered. This is to maximise the sight line of following drivers to the rear fog lamp. If two rear fog lamps are fitted, they must be symmetrical with respect to the vehicle's centreline. Proponents of twin rear fog lamps say two lamps provide vehicle distance information not available from a single lamp. Proponents of the single rear fog lamp say dual rear fog lamps closely mimic the appearance of illuminated brake lamps (which are mandatorily installed in pairs), reducing the conspicuity of the brake lamps' message when the rear fogs are activated. To provide some safeguard against rear fog lamps' masking of brake lamps, ECE R48 requires a separation of at least 10 cm between the closest illuminated edges of any brake lamp and any rear fog lamp.

Nevada Jack

Great post! Very informative.

MKW

There ARE cars with factory dual rear fogs in the US market that I've encountered from time to time on the road ( Saab , Volvo ? ,??) .

AsianML

Jaguar I know has two.

oknish

Volvo, at least my wife's 02 S80 (T6), has only one rear fog light on driver's side.

Kaumajet

So does Audi. Volvo and MB have 1.

infamily

Very helpful tool when you want someone to follow you in night.. We have gone on weekend trips with friends where we might take two cars, and the rear fog light really helps in identifying our car during night driving.

EinMD

I have found the rear fog light to be a great tool to use if someone is following too closely at night. I will flash it and the person will typically slow to increase their distance. I don't know if perhaps they think it automatically signals that they are too close..but it has worked for me! I have found it is better that using the finger

StevethePilot

If I'm feeling particularly childish (and don't worry about risking littering fines) I'll open my sun roof and toss out an empty, un-crushed pop can. They don't know if it's full or empty, but either way it scares the crap out of them without doing any damage.

All right, I've only done this once, and it wasn't originally my own idea, but it worked really well. I'd never do it again. What I do these days is either go exactly the speed limit or just let them pass me. Let 'em kill someone else. I have done the "slow rapidly for my turn" routine and actually had a guy in a C-class honk at me like it was my fault he was tailgating me.

Nevada Jack

Quote:
If I'm feeling particularly childish (and don't worry about risking littering fines) I'll open my sun roof and toss out an empty, un-crushed pop can. They don't know if it's full or empty, but either way it scares the crap out of them without doing any damage. End of Quote.

"Do this only on a closed course and the driver should be a professional idiot. Do not try this on a public road!"

Whoa Steve...you were really kidding you tried this...right? Reaction by the following driver could have been catastrophic. I don't like tailgaters but there must be a better way...:-)

Comfy_Couch

I'm pretty sure my '05 A6 had dual rear fog lamps.

StevethePilot

I do not defend it. We were the only two cars on the road, we were doing about 25 (in a 20), and I was quite young and stupid. No defending it.

Oh, and I knew the guy and he was the one who told me I should try it. Didn't make him any less peeved at me, but still, indefensible.

Spursy

Audi has 2 as well, and the Mini Cooper also has 2 rear fog lights but they are low in the spoiler below the bumper......as opposed to being integrated into the tail lights on our new MB. As a new owner....I also thought one was burned out so my wife emailed the dealer...:>)) OOPS! LOL