Hi all,
Bit of a strange one, and this has done it since I got the car 2 years ago! It's a UK 2004 2.8CRD auto, with climate control module.

Most of the time I have this on AUTO low, and let it sort out the direction of air, blower speed, etc. Now this is fine, except it NEVER changes the direction of air-flow, it always sits right in the middle (right hand air-flow adjuster, LED on the top/middle). It does appear to vary the blower fan speed though, so it does try and regulate temperature (albeit badly as sending to windscreen doesn't warm the car very quickly!)

This constantly goes to de-misting the windscreen and the feet compartments, it never changes this and blows to the normal vents, etc.

If I switch it out of AUTO and change the direction, I hear the vents change and it does blow out the normal vents, so they all work, etc, so to me it seems like the cabin sensor/temperature unit isn't sending the right signals, etc.

Now, I've had the dash apart quite a few times, and each time I've always been careful to re-connect the little sensor that sits between the two top air-vents. I assume this is the IR sensor for the climate control, but not sure. Can anybody confirm/deny if thats correct, and if that is where I should be focussing my efforts?

A few pointers would be much appreciated folks.