Does anyone know how to adjust the headlight?

j4gg4

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2013 B-class with stock xenons.

One side the headlight is sticking up and people in front of me on the roads are getting really annoyed at me.
 

V6Matty

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Small Allen key to adjust usually top and back of the headlight assembly for up and down and then another for left and right.
One thing to check that the self levelling system hasn’t come adrift, when you first turn the car on do both your lamps still do the little “dance” (down, up, led, right)? If it is then just adjust as above if not then you’ll need to be a little handy to get to the mechanism as I believe they are a real PITA to get at
 
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j4gg4

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Small Allen key to adjust usually top and back of the headlight assembly for up and down and then another for left and right.
One thing to check that the self levelling system hasn’t come adrift, when you first turn the car on do both your lamps still do the little “dance” (down, up, led, right)? If it is then just adjust as above if not then you’ll need to be a little handy to get to the mechanism as I believe they are a real PITA to get at

Thanks for the info.
I have just had time today to check to see if the lights adjust and level out on the turn of the key.
Unfortunately the one thats playing up did not move at all. So it seems a manual adjustment won't do anything? and it is potentially the self leveling motor at fault?
 

Wighty

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Thanks for the info.
I have just had time today to check to see if the lights adjust and level out on the turn of the key.
Unfortunately the one thats playing up did not move at all. So it seems a manual adjustment won't do anything? and it is potentially the self leveling motor at fault?
Self levelling fault would affect both headlights ?
 

EmilysDad

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Self levelling fault would affect both headlights ?

there could still be a fault with the individual headlight. On the Omega I had, it was a common problem that a plastic part inside the headlight that connected the motor to the reflector failed which meant the headlight shone onto the floor & the reflector was loose inside
 

V6Matty

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Thanks for the info.
I have just had time today to check to see if the lights adjust and level out on the turn of the key.
Unfortunately the one thats playing up did not move at all. So it seems a manual adjustment won't do anything? and it is potentially the self leveling motor at fault?
Might not be the motor that’s failed but I think your going to need to take the light out and see what’s going on, could just be the arm that’s come off or something simple
 
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j4gg4

j4gg4

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Thanks guys,

So I went out to it today and both lights appear to be moving and working.

I hooked up my launch pro diagnostic scanner and did a actuation test on the xenon up, down and centre. Everything worked.

Will have to put it all on hold again and wait to see if it happens again.

I did have a STORED code as follows:

In unit: SG-SW_L - left headlamp
Fault: B168901 The actuator motor for the RIGHT headlamp range adjustment has a malfunction. There is a general electrical fault.
 

mattkh

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Put it down to the extreme weather. Could the motor have had some moisture? But that normally blows a fuse.
 

Botus

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these days maybe on a cars a bit newer, wouldn't surprise me if it needs a software update - a lot of the Focus Mk4s have a similar issue, buggy software and confused cars.

another obcoius cause

there will be level sensors on the car that feed info to the headlamps, and they can fall off / break and as Emily's dad suggested the headlights can fail internally.

dependant upon the suspension system fitted, if its got air suspension it will have a level sensor on both front suspension units and one at the back, but unless you see the ride height is a long way out on one side its unlikely to be this. Likewise if it has real springs like a grown up car, then there will be one level sensor on the front and one on the back (I expect) but you'd expect both lights to be equally muddled in either suspension set up if these where the problem. These days our roads and metal from cheap parts of the world cause real springs to fail too.
 

Botus

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just read your post checking things out...

I wonder if you get enough moisture in there, could it freeze and restrict / jam the mechanism ? they nod when the car starts up

the headlamp units on my car have a software update available for each - so its not exactly unusual.....
 
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j4gg4

j4gg4

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Just an update, finally managed to have a little look at it.

Error code is this:

SG-SW_L - LEFT HEADLAMP
B168901 The actuator motor for the right headlamp range adjustment has a malfunction.

Unsure whether that meant the LEFT or RIGHT headlamp as its confusing? why on earth would they say its the LEFT module and then explain it being the RIGHT light? very odd.

So I went somewhere dark and decided to adjust the drivers side headlamp as it appeared to be way above the passenger side,I got it to a point where it was a little lower than the passenger side beam, which I think is the norm in the UK? Anyway, I drove a bit and stopped, pulled the ignition out and put it back in, started the car, the beams adjusted again automatically and now the driver beam was practically facing the floor, about a car length in front of me, stopped again and adjusted so it went a bit higher. I guess its better than dazzling people, just not sure if either side are the correct height, I guess I will know come MOT time? or is there any special way I can accurately manually adjust them to the correct height?

FYI...

6mm allen key adjusts the beam up and down, theres another one that adjusts the beam left and right too.
 

V6Matty

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Might be worth going to a local mot place and ask if they can give you a hand adjusting the lights with their testing rig, that way you’ll know it’s all correct, worth £5 in beer money to someone helpful I’m sure
 


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