Quoted from ChrisLIX:I check the bulbs and they are ok. I don't have a socket cleaning stick but I used a multimeter and test the wires from the back in ohm position and it's okay.
Maybe because I am french and my english isn't so good lol
Get a bit of sand paper or something and scuff up the inside of thay light socket so it makes better contact.
Also use your multimeter and see if you are getting any voltage though that light socket when it's supposed to. It shouldn't have any until that light is supposed to be lit.