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Carrying a canoe on the roof of my 2013 E350 causes the low beams to come on even during the day. The canoe overhangs the windshield and hood. My hypothesis is that the overhanging canoe is fooling the headlight sensor to think it's dark enough to turn on the low beams. Does this sound right to you?
I don't want my low beams on when I'm driving during the day with the canoe. So I want to turn them off. I have this kind of exterior light switch:
The low beams come on in the day in the Auto position and stay on when I click clockwise to the one-o-clock manual position. If I click once counterclockwise from Auto to the 11-o-clock position, that doesn't help because it turns on the parking lights. However, if I click to the nine-o-clock P positions (there are two of them), I get what Mercedes calls left or right standing lamps. These P positions seem to turn off the low beams and parking lights when the engine is running, which is what I want.
But when I turn the engine off with the switch at P (L or R), the standing lamps will come on unless I turn the switch back to auto when the engine is off.
Does all this sound correct? If so, my workaround to keep the low beams off during the day when the canoe is on the car is to set the light switch to P when driving, and to make sure I set it back to Auto when the engine is off. If anyone knows of an easier workaround, I'd be interested to hear it.
This would all be so much simpler if MB simply had an OFF position for all the exterior lights . . . just as I (and all my ancestors) had on every single car I owned before this one.
You shouldn't have cheapened out and went ahead and got the switch with off position package. That's weird. My light switch has a 0 between the auto and manual. Looks like a feature (cost reduction) for later models.
I didn't "cheapen out" on ordering a light switch package. I bought the car as a used CPO, the Owners Manual for the 2013 E350 only shows the one type of rotary light switch I have, and the 2013 E350 sales brochure shows no such thing as a light switch package. I had no idea there were different rotary exterior light switches on a W212.
In any event, I suppose my questions relate to folks who have the same kind of rotary light switch that I do and are familiar with its operation.
But anyone can voice an opinion on whether the canoe is interfering with the headlight sensor, which I believe is mounted in front of the rear view mirror.
I didn't "cheapen out" on ordering a light switch package. I bought the car as a used CPO, the Owners Manual for the 2013 E350 only shows the one type of rotary light switch I have, and the 2013 E350 sales brochure shows no such thing as a light switch package. I had no idea there were different rotary exterior light switches on a W212.
In any event, I suppose my questions relate to folks who have the same kind of rotary light switch that I do and are familiar with its operation.
But anyone can voice an opinion on whether the canoe is interfering with the headlight sensor, which I believe is mounted in front of the rear view mirror.
The ambient light sensor is on the centerline of the car. I believe it is the small dome atop the dash just behind the windshield, but my search of the manuals doesn't confirm this.
Regardless, when you have a 3-foot wide canoe strapped above it, the shadow it casts tells the sensor it's dark outside.
Concerning the headlight switch, I believe all the facelift cars have this configuration (post #1).
Obviously... no canoe = automatic headlight work as expected and canoe = automatic headlight don't work as expected
So what's the question... move the canoe to either side, or try having more stick out the back or don't worry about your headlights being on or set the parking lights on.
Perhaps someone better versed in this subject than I can say whether the light sensor (center dashboard dome) can be coded to trigger the headlights at a lower lux than it is presently.
I believe you can se tithe light to 0 by turning the light switch left or right and back to auto quickly. Search it up! Also make sure you don't have daylights on.
My 2016 operates the same as you describe. I believe if you just leave it at the of position (P) and get out of the car you'll find the exterior lights turn themselves off after a minute or two. Have you tried this?
I agree that the canoe shadow is like driving slowly under an overpass and the lights come on. As seldom as you are driving around with a canoe on the roof of your new SUV Mercedes I don’t see that as an issue to be worried about. Just drive with the lights on. No big deal.
I agree that the canoe shadow is like driving slowly under an overpass and the lights come on. As seldom as you are driving around with a canoe on the roof of your new SUV Mercedes I don’t see that as an issue to be worried about. Just drive with the lights on. No big deal.
I agree. The more I think about this, the more I would prefer seeing headlights used on a car carrying items on the roof. The canoe in the OP appears to be safety secured. But to be blunt, you can't trust that such items are safely attached in all cases. So lights drawing attention can be a good thing, honestly.
My 2016 operates the same as you describe. I believe if you just leave it at the of position (P) and get out of the car you'll find the exterior lights turn themselves off after a minute or two. Have you tried this?
Except for one left tail light, or the right one in the next position down to the left, I use these at parties all the time when street parking out here in the almost country with no street lights. I am going to try ML350's idea tonight, didn't know that feature existed. both my '12 and '13 have the same light switch as you do, with no off position, I also think DFW and KEY have a valid point though about canoe transport.
Clearly the canoe is interfering with the sensor, bet it messes with the rain sensor too, maybe lane keep and other camera oriented features! In my case I would find that helpful, at least for the wipers!
Last edited by pierrejoliat; 04-08-2021 at 09:41 AM.
KEY's comment about driving under overpasses (I've experienced this too), and this canoe example makes me conclude that this ambient light sensor is VERY directional, aimed at a small spot in the sky, rather than measuring diffuse light all around at street level. It makes sense that the sensor looks overhead for a darkening sky (dusk/dark, or very dark rain clouds) to operate the low beams. Just making this observation...
The only reason I don't want the headlights on during the day is because I'll be driving many thousands of miles with the canoe on the car and don't want to unnecessarily burn out the bi-xenon headlights, given that I already have the DRLs on. My Saab has headlights that can't be turned off and they burn out at least once a year. There is no legal requirement in the USA for headlights or DRLs being on during the day. And a white car with a yellow canoe on top certainly doesn't lack for daytime visibility all by itself.
While the P-left or P-right positions on the rotary switch turn off the low beams and parking lights while the engine is running, they also turn off the interior instrument cluster lights and the rear license plate light. If you turn the engine off with the rotary switch on P-left or P-right, the parking lights and tail lights on the left or right side of the car will stay on until the battery drain gets too low. I read that leaving on the "standing lights", on the side of the car facing the street traffic when a car is parked, is a common practice in Europe.
I suppose all this complexity makes sense to MB engineers, but I liked the old days when you just manually operated high beams, low beams, parking lights, and off.
I've actually driven many hours through rain and sleet with the canoe on top, and the rain sensor seems to work just about the same. Perhaps that's because enough water still hits the windshield.
I didn't "cheapen out" on ordering a light switch package. I bought the car as a used CPO, the Owners Manual for the 2013 E350 only shows the one type of rotary light switch I have, and the 2013 E350 sales brochure shows no such thing as a light switch package. I had no idea there were different rotary exterior light switches on a W212.
In any event, I suppose my questions relate to folks who have the same kind of rotary light switch that I do and are familiar with its operation.
But anyone can voice an opinion on whether the canoe is interfering with the headlight sensor, which I believe is mounted in front of the rear view mirror.
It was a joke. You are right there is no such think as a light switch package. I made that up. Of course the way German manufacturers nickel and dime on every item it could be possible. It is weird that Mercedes would drop the 0 setting for no doubt cost reasons. Stupid in my opinion. They appeared to have changed it between 2010 (my car) and 2013 (your car).
So nobody here with Xentry has run out to their car to see if the point at which the sensor turns on the headlights can be changed?
The first question is, "Are you happy with the existing threshold activation of the headlights at dusk?" If the answer is yes, then there's no reason to think about changing -- or even testing -- the sensitivity of the sensor. Making it less sensitive means your lights will not come on at dusk, but at some time after.
My guess is that the factory setting has been tested ad-nauseum, and set (without adjustability) at the sensor manufacturer to MB Spec that the liability attorneys require..
10 – Rain & light sensor
50 – Night view
70 – Interior humidity & temperature sensor
30 – Multi function camera (Automatic high beam & intelligent headlamp control, lane keeping, etc.)
I believe 26 is light sensor, remaining 4 rain sensors.
I would like an adjustable sensitivity level as I've had in some other cars. My car behaves like there is more to it than just the sensor. It will run the headlights in the blinding morning sun, but hold off on activating them in the evening until it is much darker than it was that morning. Makes no sense to me.
Your work around is the only option you have. Put the headlight position switch in one of the standing lamp positions while you're driving, then switch to auto when you stop.
Note that (at least on my 2016) using a standing lamp position while the engine is running also disables the DRL. So you won't have any exterior lighting at all on while driving.
10 – Rain & light sensor
50 – Night view
70 – Interior humidity & temperature sensor
30 – Multi function camera (Automatic high beam & intelligent headlamp control, lane keeping, etc.)
I believe 26 is light sensor, remaining 4 rain sensors.
OK, Thanks. So what is this "domed" sensor for, please? Top of dash, center under windshield glass. (I thought this was the headlight sensor. It appears on several sedan models, not just E-Class)
OK, wanting to put these sensor locations to bed, I parked my car on the driveway in the shade, but with plenty of sunlight overhead. Headlights were OFF.
I placed a dark blue kitchen towel over the dome on top of the dash... nothing. I then put another blue towel over the black sensor surround at the top of the windscreen (see below), and... the low beams and taillights came on instantly. Remove this towel and the lights went out after 15-20 seconds.
Proof positive that the sensor controlling the headlights is at the top of the windscreen. Also that shade around the vehicle proves the sensor is quite narrow beam, looking directly overhead. No wonder why the canoe turns on the lights. Miller Time!
I would like an adjustable sensitivity level as I've had in some other cars. My car behaves like there is more to it than just the sensor. It will run the headlights in the blinding morning sun, but hold off on activating them in the evening until it is much darker than it was that morning. Makes no sense to me.
Your work around is the only option you have. Put the headlight position switch in one of the standing lamp positions while you're driving, then switch to auto when you stop.
Note that (at least on my 2016) using a standing lamp position while the engine is running also disables the DRL. So you won't have any exterior lighting at all on while driving.
As an added bonus, having only one taillight illuminated will undoubtedly attract LEO attention who will wonder what else is happening besides a broken taillight on a car carrying a canoe.
2016 E350 Sport; Mom Wrecked the 2008 E350; sold the 2002 C320
FWIW, the headlight switch with the "0" position was eliminated in the facelift W212 (2014-2016). The pre-facelift W212s (2010-2013) do have an off position. The switches are not interchangeable - I tried. I figure it has to do with going from halogen/xenon on the pre-facelift to LED headlights on the facelift models.
I haven't found anything that suggests the sensitivity is adjustable.
04-07-2021, 08:04 PM
