Originally Posted by SixAlpha

I'm not sure it would be all that difficult, but I just don't think Hertz ever bothered before. Avis, Enterprise, National turn them all off by default, even on brand new vehicles that should have a trial going. They turn them on when a customer pays, and then turn it off again when the car is returned. I presume Sirius/XM has some sort of a back-end quick activate/deactivate system that they're able to integrate into the rental car company's software.