I am not sure on what interval they do but from what I have read online and from talking with someone I know who has one. They constantly phone home. Even when parked and turned off. This means that it will drain your battery and if you don’t drive for long enough (from what they said a week or two) then you can end up with a dead battery. Additionally, when driving, the device requires the driver to re-blow every 45-60 minutes. So the driver needs to pull over and test again otherwise their alarm will go off.
As far as what tampering prevention mechanisms they have I have no idea. I would assume they keep that as secret as possible.
Edit: the devices (at least the ones from intoxalock) require the driver to pay a subscription fee to keep the device working (about 100$/month) and also costs a 75$ fee for each time the driver needs to get it unlocked after a failed test.
If somebody is good enough to tamper with the part that checks for BAC, why not also tamper with the part that phones home? Would they even need to?
The device doesn’t just phone home while driving. It does it constantly. It’s likely that any tampering would alert the vendor and by proxy the court.
How often do these devices phone home that tapering would be detected? Surely they can’t do it that indefinitely. Or maybe they can. I don’t know
I am not sure on what interval they do but from what I have read online and from talking with someone I know who has one. They constantly phone home. Even when parked and turned off. This means that it will drain your battery and if you don’t drive for long enough (from what they said a week or two) then you can end up with a dead battery. Additionally, when driving, the device requires the driver to re-blow every 45-60 minutes. So the driver needs to pull over and test again otherwise their alarm will go off.
As far as what tampering prevention mechanisms they have I have no idea. I would assume they keep that as secret as possible.
Edit: the devices (at least the ones from intoxalock) require the driver to pay a subscription fee to keep the device working (about 100$/month) and also costs a 75$ fee for each time the driver needs to get it unlocked after a failed test.