headlamp adjustment

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Parrot of Doom

MB Enthusiast
Joined
Dec 13, 2005
Messages
1,101
Location
Manchester, UK
Car
1997 R-reg W210 E300TD saloon
How do the black knobs on top of the headlamps work? Trying to track down a failure of the levelling system (manual, not self-levelling)

1997 W210 saloon, halogen lamps.
 
Hi

The manual adjustment from inside the car works on a vacuum, the knobs on top of the lamp i am fairly sure have nothing to do with the vacuum the just adjustr the lamp mechanically.

230K
 
The black knobs on the back of the headlights are for directional adjustment of the beams. The upper knob gives vertical adjustment and the outer knob gives lateral adjustment.
Regarding the vacuum system, the feed on my W202 is by a violet coloured pipe to the nearside headlamp and then across to the offside headlight, check that the connections to the headlight are intact as they are easily damaged or dislodged especially when working near the back of the indicators.
Hope this helps.
 
Thanks, I just wanted to check that the lights weren't at the extent of their travel and 'struggling' hence the refusal of the level control to work.

Tomorrow I'll have the level control out and check its connected up fine, if thats ok then I'll remove each headlamp unit and do the same. If they're all working fine, my only option is to manually aim the headlamps higher as they're pointing down too far and nighttime visibility is awful.
 
I also have a 1997 W210 and the lights are very poor compared with the W124 model.
The headlamp adjustment can be tested by parking close to a garage door or a wall and moving the adjuster on the dash from position 1 to 5 with the the engine running.
You should see the beams move up and down the wall slightly, they don't move a lot.
If this is OK then adjust using the top black knobs on the rear of the headlamps equally to set the static low beam hight.
Note. The high beams are in the smaller inner lamps with the sidelights.

Lood luck

Karl
 
Sorted it. I managed to pull the undertray from above the pedals, and reach in to check. There are two pipes, hard plastic (not rubber), one violet and one pink. These two pipes both plug onto the back of the height adjuster wheel.

They were both connected up perfectly. Apologies for the poor image quality, its very difficult to get a good photo but you can see the pipes, and the handbrake cable - this gives you a good idea of where they are.

height%20adjuster.jpg


I then looked in the engine bay, immediately recognised the same pipes (before, I didn't know which was which), and went to work. The nearside pipe runs down the nearside wing and is easy to see.

nearside%20pipe.jpg


Obviously it was disconnected! So I rooted around behind the nearside lamp, and found where it should go. Basically, below the electrical connector for the lamp (on the outside edge of the headlamp unit), are two receptacles. Both were unoccupied. I quickly found another pipe lying below the headlamp, and presumed that this ran to the offside headlamp.

both%20plugs%20in.jpg


So I plugged both in, and moved over to the offside headlamp, where I found yet another purple pipe, disconnected! The receptacle (there is only one on this lamp) is in the same place, below the electrical connector.

Once everything was plugged up, both lights moved up and down perfectly. I reckon I'll have to wait until tonight and fiddle with the heights of both lights.

Its amazing that at some point in the past somebody has had the lights off for whatever reason, and completely missed these pipes!

Anyhow, one last question. Could someone do me a favour and check that I've connected the nearside pipes up the correct way around? I don't think it makes a difference but I'd just like to be certain. The long pipe is coming from the nearside wing in the second piccie.
 
C class Headlight adjusters

The adjuster are very stiff to turn & it is easy to reach the end of travel & shear the screw that moves the reflector. Also the reflector has a ball joint connected to the vacuum actuator controlled from the dashboard thumbwheel control. This can also come disconnected & needs to be snapped back in. The vacuum unit can be removed by turning clockwise about 30 deg.

If you break the adjusters you have to remove the headlights completely & check if the thread of the adjuster is broken. If so, you can take the old one out by hacksawing the knob off as close to the grey plastic fingers as possible then cut off the flange that is left with sidecutters. to reduce the diameter, so you can knock it thru the grey fingers. Another method ( used to remove a good adjuster from an otherwise damaged headlight, is to use tooth picks / cocktail sticks to hold the fingers out, so you can then tap the adjuster thru the mounting with a small hammer. New adjusters are availble from Mercedes dealers for £20 each, ie £40 per headlight.
If you refit the old ones or fit news ones it is a good idea to run an M8 X 1.0mm die over the threads, to properly cut the thread, which is a moulding.
After refitting it is much easier to turn. To refit, smear some vaseline or washing up liquid over the knob end, then push it thru the headlight unit from the front then tap it thru till the fingers snap around it. It is very easy to snap the greay fingers so take extreme car.

I am thinking of getting my local machine shop to make some replacement adjusters in stainless steel or brass, which would be much more robust & not break. If any body is interested, they can contact me
 
Excelent post, read it a couple of times but the only bit that sticks is

" smear some vaseline or washing up liquid over the knob end, then push it "

I'll get my coat......
 
If youve had this car for a while and just noticed an issue (and now fixed :)) someone may of swapped your headlights over?
 
...The vacuum unit can be removed by turning clockwise about 30 deg......

Could you elaborate further? I got as far as turning it as above, and though it did 'unlock' I can't get it off. It still seems to be partially locked. I don't want to use too much force as that could snap some plastic.

REASON:
I found the vacuum adjustment had no effect and proceeded to find the purple hard plastic vacuum lines were disconnected at the headlights & plugged. Further research reveals the left headlight vacuum unit has a leak...So proceeded to try and adjust manually (with the knobs), but the lights though do move a bit upward are still pointing far too low. Obviously the entire system is messed.

I intend to remove the vacuum unit (try and DIY repair) or else leave it disconnected and plugged and simply adjust the lights manually, if I could get the manual adjustment high enough, which I can't as it seems to have reached the end of its travel.

In short, can anyone help me wth the process of removing the vacuum and the manual adjustment units from the headlights?

Oh yeah, btw this is the W210 E class. I figure it should be similar to the W203 C Class.

Incidentally, I also found (with help from Dieselman) that if the vacuum is allowed to leak (by unplugging the lines to the headlights and leaving them open) you completely lose power!!!

Thanks in advance.
 
Last edited:
Hi,
Be sure that when the headlights are aligned that the vacuum adjuster wheel is set at zero.
 
Ok got the vacuum unit out and also realigned the manual adjustment connectors etc. Have set it to the maximum travel upwards...Will check after dark and see if suucess is mine!
 
Hi chaps - I replaced a bulb in my 02 C32 AMG and noticed that I have the coloured 'hoses' in my car, but neither are plugged in... I have Xenon headlamps with the frosty glass... Should these be plugged into anything, or are they not applicable to my lamps and so unused?

Thanks all!

Rich
 
Xenons don't use the manual vacuum levelling. They are controlled by front and rear sensors that feed the signal back into the headlight leveller electrically.
 
Excelent post, read it a couple of times but the only bit that sticks is

" smear some vaseline or washing up liquid over the knob end, then push it "

......

Pure smutt - as usuall :D:D:D :thumb:

.
 
hi the headlight manual adjusters, are you refering to the plastic clip that the headlight slides onto is it fixed into the plastic bumper if so ive been trying to get 1 for each side but ive been told there part of the headlight i would appreciate any help
 
hi i need 1 for each side both crumpled away the fingers the whole lot

The adjuster are very stiff to turn & it is easy to reach the end of travel & shear the screw that moves the reflector. Also the reflector has a ball joint connected to the vacuum actuator controlled from the dashboard thumbwheel control. This can also come disconnected & needs to be snapped back in. The vacuum unit can be removed by turning clockwise about 30 deg.

If you break the adjusters you have to remove the headlights completely & check if the thread of the adjuster is broken. If so, you can take the old one out by hacksawing the knob off as close to the grey plastic fingers as possible then cut off the flange that is left with sidecutters. to reduce the diameter, so you can knock it thru the grey fingers. Another method ( used to remove a good adjuster from an otherwise damaged headlight, is to use tooth picks / cocktail sticks to hold the fingers out, so you can then tap the adjuster thru the mounting with a small hammer. New adjusters are availble from Mercedes dealers for £20 each, ie £40 per headlight.
If you refit the old ones or fit news ones it is a good idea to run an M8 X 1.0mm die over the threads, to properly cut the thread, which is a moulding.
After refitting it is much easier to turn. To refit, smear some vaseline or washing up liquid over the knob end, then push it thru the headlight unit from the front then tap it thru till the fingers snap around it. It is very easy to snap the greay fingers so take extreme car.

I am thinking of getting my local machine shop to make some replacement adjusters in stainless steel or brass, which would be much more robust & not break. If any body is interested, they can contact me
hi can you make me 1 for each side both crumbled away when i tried to undo the screw with the plastic wheel on
 
hi can you make me 1 for each side both crumbled away when i tried to undo the screw with the plastic wheel on
hi can you make me 1 for each side both crumbled away the fingers the lot where it slides into tried undoing the screw with the plastic wheel adjuster on just fell apart
 
hi can you make me 1 for each side both crumbled away the fingers the lot where it slides into tried undoing the screw with the plastic wheel adjuster on just fell apart

ventech hasn't visited the forum for over 20 months so I doubt you'll get a response. :dk:
 

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