How to repair cloudy headlamps.
Most Mercedes-Benz headlamp lenses from 1996 onwards are plastic or to be
more accurate acrylic. Great idea as they no longer crack when a rock
flies up and hits them. The down side however is that on cars that spend
most of their time outside the headlamp lenses go cloudy.
The reason for this is that being acrylic them will get brittle when
exposed to the UV rays from the sun, so they have a UV protective coating
on them to stop this. Kind of like us putting sunscreen on when outdoors.
It is the breakdown of this UV coating that makes them look cloudy and
loose there efficiency for lighting your way after dark.
To repair this correctly there are two solutions, new headlamps as on
most versions you can't buy the lense as a separate part. Or the
far more cost effective solution of MB Spares & Service repairing the
There are a range of polishes on the market that just attempt to polish
these damaged coating, our experience is that these don't work and
in fact damage the lenses. This is explained further below.
The steps to repair the lenses are as follows:
- Remove from vehicle, or tape around surrounding panels.
- Use a cleaner to wash lense. You do not want any dirt on it when you
start the next step.
- Use 400 grit wet and dry sandpaper and remove all of the old coating,
you will know when you have got down to the acrylic of the lense when you
get a white milky residue from sanding.
- Now you need to get rid of the 400 grit sanding marks, so you need to
use 800, 1000, 1500 and then 2000 grit paper to get the marks out as you
go up each grit size the lense will start to get clearer.
- Then you polish the lense with a fine polish, now it will start to
look reasonably clear.
- Then and only then can you reapply the UV coating which will totally
restore the lense to look like new.
- Leave to dry for 4 hours and reinstall to vehicle or remove tape.
MB Spares can restore your lenses to look like new. The sanding process
will take at least 30 minutes per headlamp, maybe longer on badly
affected headlamps. The sprinter headlamps in the pictures to the right
took us over 2 hours from start to finish.
If you would like to us to repair your headlamps please
contact our service department.