Replaced battery on our 2009 S80 about 2 months ago. Yesterday I went out to go to the store and the car was dead. I jumped the battery and let it run. Battery still dead. Scheduled appointment with dealer, and they ran a check for $130. Told me that the battery went dead because the entertainment system was constantly looking for a satellite to connect to after the car was off?????? They had to download an upgrade to the system for $26.97...they said if it didn't work, I'd have to replace the entire entertainment system!!!! Thank goodness it worked, but $158 for an upgrade!!!!