W163 ML Useless Dim Headlights

Page may contain affiliate links. Please see terms for details.

91dm

MB Enthusiast
Joined
Oct 6, 2010
Messages
1,125
Location
Irl / Uk
Car
A few
Hello,

Are W163 headlights just poorly designed?

I mostly drive on unlit country roads which is fine when I've full beam on but when I go to dip I find them very poor.

I've polished the lights, upgraded the bulbs all round to osram, checked the voltage and wiring.

63981e4s-960.jpg


^Mine's the same as above. I'm thinking of fitting extra spots inside the bull bar at either side of the number plate?

Is there anything else to check?

Thanks
 
Wouldn't the extra spots set the parking sensors off?
 
Hi,
Does you're dash control work for headlight aim? Do make sure it is set at 0 (headlight adjustment always made with it set at 0).
Have you had the alignment checked? I had a similar issue on my headlights on my CLS, just because they pass the MOT doesn't mean they are as high as they can be and still pass.
I had mine adjusted to as high as they could be and still pass I think he did the left/right adjustment as well and it made a hell of a difference.
 
got a ml320 on a 2008 plate, there not good lights, had a rav4, lights were great, very disappointed in the merc lights,
 
May seem stupid but are the lights bulbs in the right way as they are very easy to install 180 degrees ie upside down and the result is very poor light output, just don't ask me how I know
 
Wouldn't the extra spots set the parking sensors off?

Mine hasn't front sensors so would be ok.

Hi,
Does you're dash control work for headlight aim? Do make sure it is set at 0 (headlight adjustment always made with it set at 0).
Have you had the alignment checked? I had a similar issue on my headlights on my CLS, just because they pass the MOT doesn't mean they are as high as they can be and still pass.
I had mine adjusted to as high as they could be and still pass I think he did the left/right adjustment as well and it made a hell of a difference.

Yes both adjusters work fine and the lights adjusted at 0.

It's hard to explain, against a wall they look perfect.It feels like they're only 80% as bright as they should be, there's no distance to the light. It's not that they're pointing too low either because the ground isn't that well lit.
 
Could it be the controller unit? I've just had a new one and the lights now seem much brighter.
 
Not sure what controller units w163's have?

I measured over 14v at the bulb.
 
Is it possible to swap over the projector housing from another headlight such as a w211 that would have better dipped headlights?
 
Your only option is to fit a after market xenon kit, these bi-xenon lamps are generally poor.
 
MB bi-xenon is generally poor? I must live on some other planet then.

91dm, does your car actually have bi-xenon or halogen projectors?

If it has the halogen one, you may buy some "Phillips X-treme Vision +130%" bulbs for an easy solution. Or you may as well purchase a set of quality bi-xenon projectors (genuine W163 ones or something like the Morimoto FX-R) and a xenon kit, since you're willing to put some money into this.

If it has the bi-xenon projectors, then there are only so many variables in the equation - bad bulbs, hazy headlights, burnt projector, poor alignment. You polished and ruled out bulbs, what's left is to get an alignment, measure beam brightness and check the projectors' reflectors for burn marks. It does happen occasionally.

I'd go to a place that can align and measure the light intensity of the beams. Then you'll be sure your lights are throwing lumens where you need them, and whether the output of the bulbs actually makes it to the road or not. If your projector is burnt, again your best option is to buy a new quality set like the ones mentioned above and have someone install it in your headlight.
 
Last edited:
Thanks for the ideas.

Mine has halogen projectors fitted. I don't think bi-xenons were ever fitted as standard or I have never seen a w163 with them. I don't want to go down aftermarket xenons again.

I read about the inside of the projector lens possibly being dirty. I checked mine today and they seem fine, no real dirt/dust. I also checked the bulbs and don't see how they could be upside down.

Any other things to check?
 
It's been asked already but I don't see an answer to the question so I'll ask it, are you sure the lights aren't the right way round?

It's a very easy mistake to make, and alters the light
 
Yes I checked this and don't see how they could be wrong as there is little cut outs/slots that the bulb sits into. The bulb is seated flat and tight.
 
Hello,

Are W163 headlights just poorly designed?

I mostly drive on unlit country roads which is fine when I've full beam on but when I go to dip I find them very poor.

I've polished the lights, upgraded the bulbs all round to osram, checked the voltage and wiring.

63981e4s-960.jpg


^Mine's the same as above. I'm thinking of fitting extra spots inside the bull bar at either side of the number plate?

Is there anything else to check?

Thanks

I have same model of ML and same issue. I was driving on a country road at the weekend and thought my sidelights were on it was so poor. Its the design of the reflectors (silver) nit and the lens (glass) that focus the lights beam.

I have the same ML as you. Its not a Mercedes, it has a Mercedes badge, but its built in America by Chrysler......sadly the W163 is about as German as Baseball.
 
Thanks for the ideas.

Mine has halogen projectors fitted. I don't think bi-xenons were ever fitted as standard or I have never seen a w163 with them. I don't want to go down aftermarket xenons again.

I read about the inside of the projector lens possibly being dirty. I checked mine today and they seem fine, no real dirt/dust. I also checked the bulbs and don't see how they could be upside down.

Any other things to check?

Let me ask, have you noticed a decline in beam brightness or has it always been unsatisfying?

The lens could very well be dirty, but if it's that dirty that it affects light output, it would be noticeable. It's also a smart decision not to put just any HID kit in there. Halogen projectors are generally made of carp and the optics are not the same anyway.

As I said - you really have only two viable options. One is to buy high-output halogen bulbs. These are generally quite expensive as far as halogen bulbs go and I have a feeling that they won't cut it for you. Your best move would be to purchase a quality HID kit with a set of good bi-xenon projectors. You have to see it to believe it - these things blow most factory HID headlights straight out of the water - both in depth and in breadth of the beam.

I have factory xenon, which is very good. However, after driving through a few country roads in complete darkness lately, I ended up ordering these (look around 3:40): https://www.youtube.com/watch?v=Db7e2W3XrZY&t=220

Other than that - you can crack open your headlights, clean them and fiddle around with questionable results.
 
They've always been poor, only improved slightly when I swapped the bulbs. The 'cleaned' drivers side is now no different to the passengers so it has ruled dirt/dust out.

Which high-output bulbs would you recommend? I've the best osram bulbs in the main and philips ultimate something in the dip.

The w202 has factory xenons so I know how good they can be. I'd prefer to stick with halogen bulbs as the ML doesn't have any self leveling system fitted to the lights.

I've read a few people who have commented that the standard lights are poor without any way of improving them.
 
I had a car with really poor dipped lights as well. Swopped them out for Philips 130% brighter bulbs and the difference was almost like night and day.

Now there is a newly released Philips 150%, the best money can buy (but with shorter life due to it's greater intensity probably)

Review here
Best car headlight bulbs: 2016 group test | Auto Express
 
Mine hasn't front sensors so would be ok.



Yes both adjusters work fine and the lights adjusted at 0.

It's hard to explain, against a wall they look perfect.It feels like they're only 80% as bright as they should be, there's no distance to the light. It's not that they're pointing too low either because the ground isn't that well lit.


I don't know whether you have sorted yours yet, but mine are the same and I'm researching what i can do,

I think it might be down to the projector reflector in the light housing, (projector burn out) i have taken the projectors out and polished the lens, inside and out, don't polish the reflector as the silver comes off, (I'm waiting for my replacement) and refitted them,

This seams to help a lot but still not great, I'm looking at finding another projector unit as all car makes use lights made up of the same components in different housings, Eg Hella E55 projectors but these are bi projectors (high low beam)

I will report back with my findings
 
No didn't reach any conclusion, I also polished the lenses/cleaned the internal housing.

I ended up buying a brand new light to see if there's any difference in new/old. I haven't got around to fitting it yet but I was thinking the same regarding burn out.
 

Users who are viewing this thread

Back
Top Bottom