I haven't found any information on when or how the trunk battery in the 2015 Malibu should be serviced. What's the situation on this? I wouldn't want to wait too long and find out the auto-start operation isn't working.

Update: The dealership says that if the trunk battery goes bad, there's a "service battery" light that should illuminate on the dashboard. If the trunk battery goes bad, the car is not going to leave you stranded at a stop light and not restart
the car. The dealership said the auto-start operation would be disabled and the car engine would not stop when you come to a traffic light.