Subprime auto lenders have adopted a dystopian method for extracting payments from their customers: installing remote GPS trackers and kill switches into borrowers' cars. The so-called starter interrupt devices allow lenders to remotely disable the ignition until borrowers return calls from debt collectors. The devices can also alert lenders to signs of trouble — for instance if the borrower is no longer traveling to their regular place of employment. Some borrowers say their cars were disabled when they were only a few days behind on their payments, leaving them stranded in unfamiliar neighborhoods or stuck in traffic at a stoplight. The volume of subprime auto loans is growing quickly and reached more than $145 billion in the first three months of this year.