Poor Light Emission from Mercedes Headlights

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I have a 2017 220d with standard headlights (no LED/ Xenon). I do a lot of lane driving when travelling to my office, and in the winter months, the light dispersion from the headlights is pretty useless. I upgraded the bulbs to new ones that are supposed to be 150% brighter, but they actually seem even worse. When on the lanes in the dark, the headlight dispersion gives me what looks like a about 10 yards in front of the car, and about the width of the road. Very poor in comparison to my other car which gives is at least double that and hits way past the verge on both sides of the road. With High beams on, the GLA lights up the road like daylight. I wondered if the wrong bulbs had been changed, i.e. the new brighter bulbs put in the high beam lights. Yesterday, I stopped in a lane with the main beam on, and looking from the front, they do seem very bright, so I'm wondering why they don't seem to be very bright from a driving perspective? Anyone else suffer from this, or have any ideas to improve the light dispersion? Thanks.
 

Lord Tyrion

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Have you checked the angle of the dipped beam? Is it pointing too low? If you can raise them then you may be able to judge if it is still rubbish.

If it is still poor when lifted and the bulbs are new then it may be something to do with the housing not reflecting out very well. You are beyond my knowledge at that point and may need to speak to your dealer. Have you looked on a Mercedes forum? They may guide you as to whether this is a common issue or whether your lights are the exception. Weirdly, you want it to be the latter. I used to have a Volvo S40 many years go. Full beam was brilliant but dipped was like having two candles in the headlights. I upgraded the bulbs but never resolved it. It was a common complaint, just a rubbish housing by Volvo. Hopefully Mercedes are better on that one.
 

clubchamp98

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I have a new VW T Roc and the lights are useless they just don’t seem to have any range.
Is it about the oems tinkering because of cost.
 
Thread starter #7
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Have you checked the angle of the dipped beam? Is it pointing too low? If you can raise them then you may be able to judge if it is still rubbish.
Googled on Mercedes lights being too low and seem to have a lot of people experiencing the same thing, even quoting the same distance - seems it is common across a lot of Merecedes models. Thanks for that LT, will go find the adjustment and see if I can raise them up
 

drdel

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I'm assuming you lens has not become 'cloudy' as some plastic covers frequently do!
For alignment drive up to within 3m of your garage door or - Cut yourself a horizontal slit about 5mm wide in a piece of card and hold another at right angle to that. Hold the slit against the light you should be able to see the line of the beam
 

DaveR

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Googled on Mercedes lights being too low and seem to have a lot of people experiencing the same thing, even quoting the same distance - seems it is common across a lot of Merecedes models. Thanks for that LT, will go find the adjustment and see if I can raise them up
This. ^^^^

I recently had a hire car with the same issue and found that the lights were adjusted right down.
 

Tashyboy

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I'm assuming you lens has not become 'cloudy' as some plastic covers frequently do!
For alignment drive up to within 3m of your garage door or - Cut yourself a horizontal slit about 5mm wide in a piece of card and hold another at right angle to that. Hold the slit against the light you should be able to see the line of the beam
This re plastic lens is a very common problem. but on a car as new as yours I would be very surprised with it being that. missis T had the same problem with this and the cloudy lens was polished out and it is as new.
 

Bunkermagnet

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This re plastic lens is a very common problem. but on a car as new as yours I would be very surprised with it being that. missis T had the same problem with this and the cloudy lens was polished out and it is as new.
I would be very worried if a Merc has plastic lenses of the type that discolour like old cheap Jap cars had.
First thing I would look at would be the manual headlight levelling adjustment.
 
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GreiginFife

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I have an E Class coupe and have no issues with lights, my C Class previously was the same, no issues.
the GLA has a reputation for the lights getting dirty quickly from road grime due to the shape of the body and aerodynamics. Not sure how much is in that. But certainly no issues here.
Now my old 3 series, don't even get me started.
 

Tashyboy

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I would be very worried if a Merc has plastic lenses of the type that discolour like old cheap Jap cars had.
First thing I would look at would be the manual headlight levelling adjustment.
I Think the problem is BM is cost and weight. But on a merc I wouldn't of thought plastic. That aside I think one of the problems with the plastic lens is parking in bright sunlight day after day..
 
Thread starter #14
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This. ^^^^

I recently had a hire car with the same issue and found that the lights were adjusted right down.
Got home last night and went stright out to check, seems I am a complete dummy. The light switch was indeed turned all the way down. I tried adjusting it, but it didn't seem to make any difference to the light projection, they didn't seem to move at all, but left it turned up. Went out later, and felt it was a marginal change in normal town driving, came home and pointed the car at the garage, from about 20 yards, and could see light hitting the door, still not as bright as I would like but better. I then turned the switch back to the lowest position, and hey presto, the lights visibly dimmed to negligible projection, turned back to the highest, and light casting on the garage door again.

I did know about the switch, adjusted it when I bought the car 3 years ago. I don't know who turned the switch right down, or when, but mad at myself for forgetting the switch existed and not trying it :oops::oops::oops:

Thanks to LT and DaveR for reminding me. Won't know until next week how much effect it will have, but I'm guessing positive because the light projection seemed to raise at least one to two feet higher.
 

Slab

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Got home last night and went stright out to check, seems I am a complete dummy. The light switch was indeed turned all the way down. I tried adjusting it, but it didn't seem to make any difference to the light projection, they didn't seem to move at all, but left it turned up. Went out later, and felt it was a marginal change in normal town driving, came home and pointed the car at the garage, from about 20 yards, and could see light hitting the door, still not as bright as I would like but better. I then turned the switch back to the lowest position, and hey presto, the lights visibly dimmed to negligible projection, turned back to the highest, and light casting on the garage door again.

I did know about the switch, adjusted it when I bought the car 3 years ago. I don't know who turned the switch right down, or when, but mad at myself for forgetting the switch existed and not trying it :oops::oops::oops:

Thanks to LT and DaveR for reminding me. Won't know until next week how much effect it will have, but I'm guessing positive because the light projection seemed to raise at least one to two feet higher.
Usually happens when someone cleans the interior and wipes over the switch/roller, same as all the other 'settings' getting mucked up
 
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