But could the disabling be done accidentally by just reaching around under the dashboard?
Late to the game and probably already answered, but in my experience, yes it can be. I guess it would depend on what type of GPS it was, but we have one for our teenage daughter and before we hardwired it, it was just plug in type and if she were to hit it with her leg, it would disable and we would receive notification via text that the system may have been tampered with.