It sounds like several of us are having similar A/C issues. Unfortunately Madeinjapan seems to be confusing the issue by giving different recommendations on different posts. He suggests on one post that the issue is caused by low refrigerant then on this post suggests it is caused by too much refrig...

Check with your dealer for status of oil trap notice from Volvo. I was reimbursed for 2 oil trap replacements one at 60k and one at 120k. Officially they reimburse up to 110k I think. I know this is on V50 not sure about S40.

I have the same problem on my V50 and the dealer just charged it yesterday. It did not correct the problem. Just had someone tell me it could be damper motors which are new equipment only in 2005 or later.

Jim