I have this problem now. Only started after it took a little knock in the snow, although I had a Pilkington screen fitted about 3 years ago too, hmm.... Its craked now from a stonechip, so will be getting changed before the mot is due. I will investigete the footwell connectors too now, thanks for the info.
Also went to Lexus today to see how much they wanted for a relay and it was £61. Luckily I think I have have secured one from ebay for £12 posted which is much more manageable right now.
Oh, and I'm a serial auto light user :)