For a real world example Subaru, when 3G shut down, their wireless modems started massively draining the battery even for people with no subscription. As it tri

For a real world example Subaru, when 3G shut down, their wireless modems started massively draining the battery even for people with no subscription. As it tried over and over again to connect to the 3G network to check if you even had a subscription. The manufacturer had (has) no good solution to this. They just change something to dealer mode and hope your battery never completely drains and resets it.