rear lights

[readie]

hi why does my rearlight keep misting up ive brought a new bulb holder dryed the light out with a hairdryer as sone as i put the thing back in it misted up 

[Shamm]

Check closely you might have a slight crack

[readie]

it only does it on the drivers side ive brought a secondhand lamp still misted up

[Shamm]

Again you should check maybe there is a slight crack

[DrG_GTi]

I had this years ago with an old clio, sometimes the plastic deteriorates to the point where hairline cracks appear, and/or the seal fails.
I sorted it by putting one of these inside, bit sh*te but it fixed it and didn't have to buy another unit.... 

http://www.ebay.co.uk/itm/like/360917050738

[lukemk5gti]

Happens to a huge number of people including myself.

My original lights had the issue and I replaced them with R32 ones again with the same issue.

Dry them out fully and then use clear silicone to seal the top and sides of the light casing with your finger.

The part where the red plastic front of the light meets the black plastic frame.

You won't see a leak but water does get pulled in.

[readie]

Did that sort the problem ??

[lukemk5gti]

Did that sort the problem ??

Immediately.

Suffered with condensation on those new lights for about 6 months.