chinhster

At a stoplight last night, I noticed my driver's side fog light on but not the passenger side one from a reflection off the car in front of me. After a few minutes, the fog light faded off. Later, I started the car, got out and checked the fog lights and they were both off. Drove about 50 feet, got out, and the driver side fog light was on again. Drove another quarter mile and the fog light was off.

I thought my lights were screwed up until I checked the manual and it mentioned cornering fog lights which I guess is what's going on (the 50 feet I drove was in the parking lot of a restaurant and I was going counter clockwise heading out). I'm not quite sure what good turning on just one fog light does and if anything, is probably distracting to other drivers. I find it unattractive because it looks like you've got a broken fog light if just one of them is on.

The thing I really don't get the point of is the separate left and right standing lights settings. How is that useful?

roger23

Chinhster, you obviously have the active headlight package ( also on my ML500 ) . It took me a little time to figure what was going on , but this is what happens:
At low speeds at night, (below about 10 kph ) when you put on your left turn signal, the light in your left fog lamp ONLY, comes on to illuminate the left side of the road on an angle, anticipating a left hand turn i.e. acting as a cornering lamp. When you have completed the turn, the lamp goes out. The same thing happens on right turns, with your right fog lamp. Neither will illuminate on highways etc. when changing lanes etc. to eliminate confusion to other motorists. At normal speeds, your headlamp lights swivel in the direction you are turning the steering wheel to help illuminate you intended path of travel. Also, at night , these fog lamps will illuminate separately at very low speeds when executing sharp turns, whether or not you have put on your turn signal i.e. turning into your driveway.

benzmodz

I have never heard of active cornering Bixenons in an ML or C but I could be wrong. Active foglamps are quite common and can be activated on all 2005 cars.

GregW / Oregon

I think the foglight may give a little more illumination of curbs, driveways, etc. when cornering at low speeds, but I agree that activating only one looks screwy and does result in people telling you that one of your lights is out. I noticed it the other day when my wife drove in and almost went out to check the lights until I remembered. Why not just turn on both? I bet there's a simple way to do modify them to do this.

The left/right standing lights are used when you are parked along a narrow street at night, for instance, and want to make your vehicle visable without running down the batttery too much. That's been a common European feature for over 30 years (my '73 BMW 2002 had it).

AutoSaurus

I really like this feature but I do get comments often about having a burnt out bulb.

GregW / Oregon

It is a new feature on the ML starting with this model. It is optional (I think it should be standard, like on the new BMW 3-Series) with the Lighting Package, which includes the xenons and headlight washers, as well.

"Active Light System: The headlamps follow the steering movements of the driver and rapidly pivot to the relevant side when the car enters a bend. This improves road illumination by up to 90 percent: whereas the normal illumination range when entering a bend with a radius of 190 metres is around 30 metres, this increases by a further 25 metres with the new headlamp technology. Because the light distribution corresponds to the current steering angle, the driver recognizes the course of a bend sooner than with conventional low-beam headlamps. Active headlamps work on both main and low beam."