I have the AWD 2.0 ltr petrol model with auto LED headlights and lane departure warning etc.
On my drive home last night in cold and potential freezing fog conditions (3 deg C) the auto dipping system played up by not dipping when it should and two warning lights came on: Auto Headlamp and Lane Departure. On close inspection when I arrived home I found the inside of the windscreen under the sensor area had fogged over, so the sensors could no longer "see".
I thought this area of the windscreen was sealed off to stop moisture getting onto the inner surface of the glass to prevent this potential issue. So my question: has anyone else seen this issue, and for the tech guys is it likely I have a fault in that the seal round the sensor area has got a leak?
I've had similar experiences twice in high humidity but didn't think to look inside that sensor area. I'm no expert on this specifically, but I'd guess that having that area unsealed to allow air flow to dry it would be better/easier than trying to keep it perfectly sealed to keep moisture out.
As an FYI, I noticed this weekend that a build up of around 3/8" of slush and/or ice on the front emblem/sensor prevents it from working properly.
I sometimes used to have this problem soon after start up. I now make sure the headlight stalk is in the dipped beam position, put the a/c on demist and leave for 10 to 15 minutes to make sure the windscreen is completely clear before pusing the stalk to high beam assist. This seems to prevent the problem. If I do get the warning light I find I have to make sure the a/c is on demist, stop and switch off the car, and then restart.