Cornering Lights...

[Brian WH]

My CLS has 616 Active lights and of course Bi-Xenons.

Tried them the other day with lights on, reflected in a shop window. Anyway half a turn of the steering wheel to the right and right spotlight came on. Straightened up and briefly both spotlights came on, and then went out. Same with half a turn left. However at no time could I detect any movement of the Xenon lights??

 

[Diesel Benz]

We eventually saw our lights moving in a very quiet country lane, but it was not easy to pick up this extra movement. The thing to remember is the car moves the instant the steering wheel moves the headlights swivel, but the car also moves....... To differentiate between the small movement made by these very illuminating lights and the real movement of the car is negligible, plus when we think about it, the time taken for the car to make up any difference, is also negligible. The lights do not swivel to a 30 degree angle or anything like it.

I was convinced our active lights were not 'active' the workshops had problems finding out how to check the lights to make sure they were moving, but eventually the experts got involved and yup they work

Regards
John

I don't have active xenons on the W211 but I would estimate the W221 lights turning by 30 degrees, likely not more but they do turn a lot on a tight corner. I tried to find some official data for this but couldn't. The attached figures is an illustration, no turning angle mentioned but I assume the illustration is not showing the max turning angle (looks less than 30 degrees in the figure). Would be nice to have some "official values" and info if the W211 and W/S211 should behave the same (I would assume so).

Like the figure shows, even a small turn makes a big difference in range. 30 degrees would not be needed at highway type of corners (and there it would even be difficult to detect the lamps turning). But at lower speeds and tighter turns the lights should really turn "a lot". Still all subjective before someone can provide figures. I'm guessing our experience being more from different types of roads, more slow speed tight turns for me perhaps.

Perhaps I should try some photos from my car. Now I just don't remember if the lights turn when the car is stationary and I would not start taking photos at tight turns on the road.

 

[Diesel Benz]

OK, found the figures from W211 documentation. This is specifically for the 615 option. The maximum turning angle is 15 degrees. It would be max 15 degrees towards the "outside" of the vehicle and 8 degrees towards the inside.

Not sure at all if this applies to other W211 options and it sure feels less than I would figure for the W221 lights, would like to find the figures but it could simply be my estimation error.

 

[television]

Thanks for your input Diesel benz, in a way I feel that they could encourage you to take a bend faster than you would do without them looking at the graphs, or am I being too careful

 

[Brian WH]

OK, found the figures from W211 documentation. This is specifically for the 615 option. The maximum turning angle is 15 degrees. It would be max 15 degrees towards the "outside" of the vehicle and 8 degrees towards the inside.

Not sure at all if this applies to other W211 options and it sure feels less than I would figure for the W221 lights, would like to find the figures but it could simply be my estimation error.

I would say the diagram above shows nearer 15 deg rather than 30 deg. Must try mine again to see if I can detect movement, but as you say does it work stationary?

 

[marcos]

I would say the diagram above shows nearer 15 deg rather than 30 deg. Must try mine again to see if I can detect movement, but as you say does it work stationary?

The ones on my ML dont work when stationary Brian, I'll check the ones on my Dads CLS tomorrow but I would think they are all the same.

 

[glojo]

I would say the diagram above shows nearer 15 deg rather than 30 deg. Must try mine again to see if I can detect movement, but as you say does it work stationary?

I have the older 211 active lights but I have been down this exact, self same route. It started getting to be an obsession to see these lights working.

In real life the diagram kindly posted by Diesel Benz means nothing, as the car gradually enters the bend and the movement of the car hides the movement of the lights. The car is travelling at speed and this angled throw-off of the lights is meaningless, I am NOT knocking the system and perhaps if the headlights were useless this movement might be noticeable. The bi-xeons are exceptional and light up a dark road brilliantly

I have spoken to other 211 car owners with this option and the odd owner can see this movement, what I put this down to is driving style. If the driver somehow only drives looking at the floodlit area, then I guess it might be possible to detect the movement, but a driver that is looking forward may not notice this very small deviation.

The very early 211's (pre 2004) would always carry out a full movement check whenever the engine was started. Headlights would move left, right, up down and centre before moving off. That at least convinces the owner that the active lights are working.

If the new active lights are similar to the pre facelift, then they do not move below a certain speed, 10kph comes to mind but I'm not 100% certain.

John

 

[Diesel Benz]

I tried to emphasize that the figure was not supposed to indicate the max turning range but more about the fact that on a bend, even a slight turn on the light beam makes a big difference in the range the road is lit. Sorry if I referred incorrectly to the figure.

It does not help if the lights are good if they don't show the road ahead. When driving and looking at the road, going through and S-curve for example, one can pretty easily see how the lights turn, and come back when turning back to the straight. I guess it would be easier to see the lights turning if one would look straight all the way, but that would make it dangerous driving through the corners (but doing it as a passenger could do, this option seldom comes to my mind for some reason).

One might be inspired to drive faster to the curve when it isn't dark. This is an issue with most safety type of accessories. I would leave it for the driver to understand that it still is the same corner even if it is better lit with the new lights. I guess it would not work for all drivers but for those ones it may be no better to leave the road unlit.

 

[whitenemesis]

Found this from 2003


Mercedes-Benz Active System

Figure 3-This illustration shows the difference in light distribution between conventional headlamps (top) and the Mercedes-Benz Active Cornering Headlamp System (bottom). (Courtesy of Mercedes-Benz)

​

Mercedes-Benz uses a different approach, a totally active system, called "Active Cornering Headlamp System." With this system, the headlamps swivel in the direction of the curve or corner (see Figure 3). The system uses bi-xenon projector headlamps that have an electronics unit and electric motor to swivel the projector unit inside the assembly. The bi-xenon headlamps produce both the low and high beams from a single xenon lamp. The headlamps are controlled by a control module that receives inputs on vehicle speed and steering angle to determine how fast and how far to swivel the lamps. This system works at all speeds, and with the headlamps in both low and high beam. The system matches the speed of the vehicle, the swiveling mechanism reacting almost instantly at high speeds and progressively slower as vehicle speed decreases.

 

[whitenemesis]

And currently;

Bi-xenon headlamps with Active Light System

What could be nicer than taking a drive in a cabriolet on a warm summer’s night? With the CLK‑Class Cabriolet, this wonderful experience can now be made extra safe too. Optional bi-xenon headlamps including the active light and cornering light functions light up even the darkest roads.

The Active Light System ensures that the bi-xenon headlamps follow your steering movements. This improves illumination on bends by up to 90%, allowing you to see the course of the bend and any obstacles at an earlier stage.

Whenever you indicate to turn or take a sharp bend at speeds of up to 30 km/h, the cornering light function integrated into the front fog lamps is automatically activated on the side of the vehicle on the inside of the turn or bend.

 

[glojo]

Found this from 2003

That's the system we have, it is excellent but tgo detect the independant movement of the lights as opposed from the movement of the vehicle is extremely difficult. I think for those that have it, I would suggest it is less frustrating to just accept the illumination is second to none and not become obsessed with trying to see the headlights move.

Those that don't have the system tend to submit links or advertising information which very kindly illustrate how the system works but when we stop and think how little steering movement is required to negotiate a bend, and the car instantly responds to the wheel, it is very hard to expect the human eye to detect a very slight movement of the headlight beam that is out of synch with the turning movement of the vehicle.

John

 

[Diesel Benz]

Since I have those swiveling lights on my W221, may I add a few comments to my previous ones.

First, the marketing material cannot be that complex and cannot cover all details (on the other hand they pick up the details to be left, to make things look better). Anyway the system would try to detect driving on a straight road and would hardly adjust the beam for steering wheel movements of +/- 6 degrees (which is quite a lot). The response speed is asymmetric, as well as the max turn angle. It is also speed sensitive.

I would say that the design is perfect if the driver doesn't notice the movements, they are not there for entertainment. The task is to have the road lit.

I had a look at Hella documentation (for after market lights) and they also have the 15 degree maximum figure, I believe that must also apply for my car too. It may feel even more at tight turns (but I have not found any other figure for the W221, I assume some EU regulations even exist and set a limit).

Meanwhile I tried turning the wheel quite a bit when driving a straight road in the dark (alone). I'm pretty sure the lights did not turn at all (within the space I had on a 2 lane small road).

Now we are talking about more than 2 different MB models, I only have experience from a W221 (with turning xenons) and I insist that it is very easy to see the lights turning at tight corners when driving with main lights in the dark. Even if it was only 15 degrees, it really helps on 90 degree corners (at country side where a 90 degree corner takes some space).

I repeat again that I do agree with glojo that the basic light strength (not only intensity but also the dipped beam width off the road and such) of the xenons is more important than the dynamic turning feature.

 

[whitenemesis]

Just discovered something else I didn't know.

When turning whilst reversing the outside cornering light illuminates. i.e. reverse left and the right fog lamp comes on.

 

[television]

Just discovered something else I didn't know.

When turning whilst reversing the outside cornering light illuminates. i.e. reverse left and the right fog lamp comes on.

Can you please post it again in the morning, I cant take it in tonight

 

[whitenemesis]

Since I have those swiveling lights on my W221, may I add a few comments to my previous ones.

First, the marketing material cannot be that complex and cannot cover all details (on the other hand they pick up the details to be left, to make things look better). Anyway the system would try to detect driving on a straight road and would hardly adjust the beam for steering wheel movements of +/- 6 degrees (which is quite a lot). The response speed is asymmetric, as well as the max turn angle. It is also speed sensitive.

I would say that the design is perfect if the driver doesn't notice the movements, they are not there for entertainment. The task is to have the road lit.

I had a look at Hella documentation (for after market lights) and they also have the 15 degree maximum figure, I believe that must also apply for my car too. It may feel even more at tight turns (but I have not found any other figure for the W221, I assume some EU regulations even exist and set a limit).

Meanwhile I tried turning the wheel quite a bit when driving a straight road in the dark (alone). I'm pretty sure the lights did not turn at all (within the space I had on a 2 lane small road).

Now we are talking about more than 2 different MB models, I only have experience from a W221 (with turning xenons) and I insist that it is very easy to see the lights turning at tight corners when driving with main lights in the dark. Even if it was only 15 degrees, it really helps on 90 degree corners (at country side where a 90 degree corner takes some space).

I repeat again that I do agree with glojo that the basic light strength (not only intensity but also the dipped beam width off the road and such) of the xenons is more important than the dynamic turning feature.

Could the above be due to assistance from the cornering lights?

 

[retrospek]

I'm still undecided about the cornering lights on my new car (W211). I went to Derby early yesterday morning and on the way I stopped at the Services. When I was driving out of the Services Car Park going left and right my car was lit up like a Xmas Tree

 

[whitenemesis]

When cornering lights go out they fade slowly ~3sec. Very different to other lights

 

[Diesel Benz]

Could the above be due to assistance from the cornering lights?

Not in this case, the cornering lights do not fire at low speeds.

 

[whitenemesis]

Not in this case, the cornering lights do not fire at low speeds.

Mine come on at speeds below 40kph, either when indicating or turning the steering wheel >90deg

 

[glojo]

Mine come on at speeds below 40kph, either when indicating or turning the steering wheel >90deg

The older style 211 will come on at just over walking pace. I was a fast walker 10kph rings a bell

John