Headlights steaming up

[Lukeyboy2k]

well my facelift ones are near enough brand new and still do it

 

There are a number of factors which can affect this. Some more obvious than others.

 

1) Dodgy seal between plastic/glass and rest of housing.

2) Dodgy seal between bulb holders and housing.

3) Relative humidity, temperature, pressure, of environment used to store headlight prior to fitment compared to same variables outside when the units are installed.

 

In an ideal world, points 1 and 2 would be addressed (i.e. perfect seals all round), the lights were stored in warmish, dry conditions under slightly elevated pressure. Then you would install the lights and bulbs on a very nice dry, warm sunny day. If this procedure was followed, there should be no misting or condensation.