Fitted new headlights, now all fogged up!!

[Governor]

Fitted a new set of headlights to the vectra just before xmas as the old ones had really bad condensation inside them, like a waterfall in N/s, now after only a few weeks, my new o/s one has gone bad, got a lot of fog inside! really peeved with this, any ideas why??

[RBH]

put in the small bags of silica....you know the ones that you get in shoe boxes or electrical items..............these do the trick mate

[spennny]

Did you seal them up at the back correctly ?

[bigdave1701]

They'll be fogging up because moisture's getting in somewhere. Take the caps of the back and put a towel over the headlight then put the main beams on for half hour. That should be enough to burn the condensation off and allow most of it to escape out the back. Then get a bag of silica gel, tie a bit of string round it and pop it in the back of the lights before putting the covers back on (leave the string hanging out so you can get the silica back out again). If it fogs up again, you need to look at where moisture's getting in and seal it up.

[rich r]

You must have the rubber caps on the back. If they're missing, or have holes in them (eg for HID cabling) then the lenses will mist up.

I had to un-mist mine when I bought the car a year ago, and they've been fine ever since. My method was to take out all the bulbs (gives more paths for the damp air to get out) and shine a 150W halogen lamp at the front of the headlight to gently warm it up (don't go too mad, the headlight is only plastic). Then after an hour or so, all the condensation was gone. I refitted the bulbs and the rubber caps, making sure they sealed properly.

[Governor]

Thanks for the replies, yes got HIDs fitted so have cut a cross in the rubber covers for cables, will look at that and try the silica gel too!! Thanks