I have an 05 S60 and had the same thing happen. Try getting your tires rotated and balanced. I think the balancing is what fixed my issue. Good luck.

I have a 2005 S60 2.5T AWD. It is approaching 100k miles. It has manual climate controls. It has recently stopped blowing out heat while when the "Auto" button is on (and the A/C is turned off). If I turn the knobs from hot to cold still with the A/C off, it suddenly blasts out cool air. T...