I just bought a used 2008 XC90. My brother in law checked the car out mechanically and it stacked up so he bought it for me. When I got the car I did the first thing most new car buyers do, I checked out the radio to see just how great the sound system was. Reading reviews on the XC90 high praise was given to its sound system. I was shocked to find that the only sound I really heard was coming out of the speaker in the middle of the dash. I at first wondered if the sellers might have removed the speakers from the car. We started to mess with the adjustments. There was no bass response as we went up and down, no treble either. We could get the front door speakers to seem to work but you could barely hear them. Nothing from the back seat speakers and when putting it all the way to the very back at the hatch you could hear them but barely either. So I thought bummer we are going to need to get a new sound system in this car. As I began to do research I discovered all the information about what happens when you have a bad ICM. Wish I had of known to look for this kind of problem before I bought this particular used XC90. I am highly suspicious this is why the car was sold by the seller, but I can't say. Anyway from past experience does this sound like what the problem is? The ICM? Right now the navigation still works fine and the back up sensors on the car. I am having no issues other than the fact it sounds like the speakers are blown or gone from the car, as I said only the middle dash speaker really has any volume. I want to be proactive and get this fixed before any real problems occur that I have read about with the ICM or other connected parts to the overall system it is linked too.

 

You have at least one functioning speaker. I would start by removing the center speaker and then popping the panel off either the driver or passenger door and plugging the known good speaker in its place. This would start to rule out whether it is the speakers. Alternatively you can purchase a used speaker on ebay rather than pulling the center speaker. If not the speakers then it is either the amp or the ICM. I have an 04 that I picked up last year. I replaced amp, speakers and ICM with parts from donor cars that keep coming into the local Pull-a-Part. Getting used parts is certainly an option.