Visteon Headlamp Adjustment

[Dyane6]

I have a 2004 Multispace which has a Visteon offside headlamp. Looks as though it was made in Czechoslovakia according to the sticker.
I have tried to adjust the horizontal aim using the 6mm a/f screw which is located beneath the main wiring plug which has the red release button.
First problem was getting the adjuster to turn at all.
It is made of plastic and even a 6 point socket turned without rotating the screw. I finally got it to turn after I shimmed the socket to produce a tight fit.
After all that, when I turned the screw in , the headlamp beam moved upwards not sideways.
I tried turning it in the opposite direction but I could not make it move.
Does this sound familiar to anyone out there?

If I keep trying to turn the screw, it may shear off altogether which will no doubt cost me an arm and a leg to buy a genuine Citroen lamp.

[jonnie100]

headlight adj pdf here if it helps:
http://www.berlingoforum.co.uk/attachment.php?aid=499

[Dyane6]

I have seen that one thanks but it doesn't supply info as to why the lateral adjuster makes raises and lowers the beam.
Is it aproblem other owners have had when Visteon headlamp is fitted?

[jonnie100]

Is Visteon an aftermarket make?
I have heard and seen that many aftermarket headlights are terrible quality, they might look the part but build quality is rubbish. I remember buying aftermarket angel eyes for my old bmw and the adjustments didn't work at all, I found they had dummy adjustment knobs with no actual working adjustment parts inside!
Or maybe it's a genuine part and the mechanism is just knackered?
Maybe a s/h known to be working order headlight is the answer? Plenty on ebay.