on my 2010 s40 the heater box was screwing up bad. when i switch to defrost it would make all kinda noises and then finnally switch. if i tried to switch back to ac it was also messing up. brought it to dealer AND they had it 3 days now. said changing the heater box is a big job. have to take dash all apart. does this sound right ? i never had a heater box go, never mind on a 2 year old car.

 

There are several parts that are buried in the dash, but it's likely that they have a lot of work ahead of you and haven't gotten started on it. Do you have a loaner?

 

they gave me a loaner on the 3rd day. said they have several components to remove.