I have a 2006 S40 2.4l and the am/fm will not work, but the CD player works fine. I loaded the trunk up with a bunch of stuff and some water spilled (not a lot of water, just made the carpet wet). After that, the radio was just static. I can pick up the one local station, but if I drive by a large building or under a bridge, that channel fades out. I took out the receiver last night and all the harnesses are tight. I tried to access the connection on the driverside rear pillar but did not want to mess with the airbag. Are there any common causes of this? I have done quite a bit of research but have not found anything. Any ideas guys?

 

There is a problem with the intergrated audio module (or the actual CD player) that goes bad on these cars. Normally it would just kill the am radio but in rare cases the FM would also not work. That would be my guess.