LED headlight adjustment

[Craiglxviii]

I'm glad you post here Craig, you highlight the ridiculous amount of tasks that smaller outfits cant manage to do without massive investment in kit for one manufacture. My R Class is the first Mercedes I've owned. The 3 point star wasn't bought because I aspired to owning one, just that I didnt want a FWD Eurobox. The way you paint the advancement of uneccessary & stupidly complicated electronics, it might very well be my last.

They’re no different to any other car in this respect (or many other respects!)

Most OEMs only design the visual appearance of their headlamps. The rest is passed as specification only to a tier 1 supplier, who does the actual design work. NB the carmaker DOES NOT design the actual lighting part of the lamp, they just draw what they want it to look like and then give performance, colour temp etc specifications required.

There are only five main tier 1 lighting suppliers used globally. Valeo and Hella are the most popular amongst ze Germans.

In terms of smaller imdys being able to work on cars, I’d say that is quite perceptive.

 

[EmilysDad]

No. It’s done during vehicle assembly; the car is sat on a perfectly flat and level plate at a certain load condition, then the lamp levelling system gets taught the normal level position for that exact vehicle.

It’s the kind of thing that needs to be done once during the whole vehicle lifetime...

Unless it gets a bump

 

[Jeddy]

ok, so if I put the car maybe 2m away from the end of the garage and measure the height of the beam thrown at the end of the garage the offside is several cm lower than the nearside. I also know that the offside unit has been replaced (the sticker on it has a date several months after the car was registered).
I was prepared to accept that a headlight unit could have failed and been replaced, but that wouldn't have resulted in the above.
If we're saying you can't adjust it then are we suggesting that a MB main dealer sold a 1yo car which had been involved in an accident and not repaired correctly to the extent that the headlights no longer line up and didn't declare it? Maybe they didn't know.
Something else for them to look at when it goes back!
Jeddy

 

[LostKiwi]

Are you sure you aren't looking at the 'kick' of the beam?
Our Mini with LED headlights has the left side 4-5 cm higher than the right as a result of the beam pattern. If you look carefully you can see the kick of the individual lights.

 

[Jeddy]

Are you sure you aren't looking at the 'kick' of the beam?
Our Mini with LED headlights has the left side 4-5 cm higher than the right as a result of the beam pattern. If you look carefully you can see the kick of the individual lights.

I'm not sure I understand. As far as I could tell nearside and offside have the same pattern. So long as I'm measuring each in front of each headlight at their respective lowest points, surely they should be the same?
The alternative would mean different rules for nearside and offside headlights which doesn't appear to be the case.

 

[LostKiwi]

The right side and left side lights beams overlap. The left one lower edge will be under the rightly ones kick.

 

[Jeddy]

To tell the truth, there is minimal kick on these LED headlights, it's almost two flat lines, the left side of each being slightly above the right side of the same light. I have to say that seems odd to me, but I've never had LEDs before. Not ideal! However all of the offside light is below all of the near side. Maybe I need to get a photo.

 

[LostKiwi]

The minimal kick is a characteristic of LEDs.

 

[Craiglxviii]

This is a (very) stylised representation of a UK spec asymmetric beam pattern as viewed from above. The kick or dogleg is visible on the left side.


Here is that U.K. beam pattern as would be seen projected onto a blank wall. Kick again visible on left. This is what illuminates the kerb.



Here is a Euro style symmetrical beam pattern. It’s a bit more lozengey shaped in real life. No kick (rather, it’s there but not as a definable element in ortho view).



And the above projected against a wall. Kick is very slightly visible here but reality is it’s a brighter part of the beam and not an entire element as above.



Is this what you see?

 

[LostKiwi]

Essentially when projected against a wall it will look like this:

 

[Jeddy]

Thanks guys that's useful.

It's obviously light outside now so it's difficult to project both lights onto a nice clear garage door and get a good photo, however I have taken a couple of photos within the garage. Both photos were taken with my wheely bin exactly the same distance (65cm) in front of the front most (inner most) part of each headlight. Conveniently the LEDs have a 'blind spot / dark spot' which I've marked the top and bottom of on a piece of masking tape. On the LEDNearsideC350 photo you can see the pair of lines. On the LEDOffsideC350 photo you can see the lines I've drawn for both offside and above that the nearside. The nearside is approx 2cm higher.
OK, 2 cm isn't much, even at 30m it's only going to be around 1m, however as soon as it projects onto a horizontal road rather than a vertical surface that suddenly becomes many metres. Even if it is within tolerances for an MOT, I rather doubt it came out of the factory like this - I'd expect close to LostKiwi's images.

(Edit - please see a few posts below for photos, I had problems insterting here)

Thanks,
Jeddy

 

[Jeddy]

Rats, that didn't work, can someone point me to a link for how to link to photos please? I Assumed it would just be click on the image link and paste in my dropbox shared link...

 

[LostKiwi]

can someone point me to a link for how to link to photos please

Use the 'Upload a file' button on the bottom right of the posting box. By far the easiest way and ensure if anything like the photobucket fiasco happens again the images are still available.

 

[Jeddy]

First LED Nearside C350





And below, LED Offside C350




Thanks LostKiwi, I'd not spotted that! That works better and as you say, avoids problems when I eventually delete the file from dropbox.

Jeddy

 

[LostKiwi]

Ok looks like it needs adjustment as you said
Can you get an image of bonnet open looking down at the top of the light (including the slam panel)?

 

[Craiglxviii]

Yup. That’s not right. I’d suggest that the lamp needs recalibration and not adjusting btw.

 

[Jeddy]

I'm not sure if I should be concerned about this, I guess it's just a case that the unit has been replaced (as above, I know that) and not recalibrated / adjusted or if there is something more going on. Either way, it's not a good sign that the light wasn't recalibrated when it was replaced - bodge job by someone who didn't know it needed to be done or someone who couldn't be bothered to do it right.

Like this?

 

[Craiglxviii]

Just because MB Dealer did the job doesn’t mean it was done correctly...

 

[Jeddy]

Just because MB Dealer did the job doesn’t mean it was done correctly...

Indeed and the dealer I bought the car from denies doing it. I guess either:

• it failed and was replaced under warranty by MB
  
• it was damaged and replaced by insurance / the previous keeper by god knows who.

 

[Craiglxviii]

Give Colin @ MBS a buzz. He may well have the capability to calibrate your lamp.