Comment by calvinmorrison

Comment by calvinmorrison 3 days ago

8 replies

nothing. And banning ALPR wont fix anything either. All cars have 4 unique serial numbers broadcast via radio at all times via the TPMS system. you don't even need a camera, just a radio receiver.

fh973 3 days ago

Checked how to receive those with SDR. Turns out they are very low power and you need to basically touch the tire. Also the transmit in minute intervals. Bit exactly a a smoking gun in terms of mass surveillance.

ErroneousBosh 3 days ago

> All cars have 4 unique serial numbers broadcast via radio at all times via the TPMS system.

Mine doesn't.

  • calvinmorrison 3 days ago

    do you have some sort of indirect tire pressure checking like wheel speed?

    • ErroneousBosh 2 days ago

      No, I have a tyre pressure gauge. Every so often I check the tyre pressures and maybe stick a bit more in if it needs it.

      Some VWs used to use wheel speed, though, which was fun because they added tyre pressure checking with a software upgrade. Not terribly accurate, but enough to tell you if one was low.

1shooner 3 days ago

> banning ALPR wont fix anything either.

Ideally the implementation would be immaterial to a ban. The ban (or more likely first, warrant requirement similar to cell data) would be on the tracking database, not the details of how the tracking was accomplished.

jeroenhd 3 days ago

TPMS doesn't need to be unencrypted like that, although many car manufacturers do like to save a buck.

If you get a car old enough, you won't need to worry about TPMS (but that car will not have been tested against recent crash test scenarios).

  • calvinmorrison 3 days ago

    TPMS is over the air, each sesnor has a 32 bit unique ID. you have 4 per car... its easy to identify

    • jeroenhd 3 days ago

      Depends on the TPMS implementation to be honest. Most of the UHF ones are impossible to receive unless you're using some optimally placed/pretty powerful equipment. Even then, the protocol is entirely up to the vendor, as long as the system is reliable.

      My car is old enough that it doesn't have TPMS sensors but I have looked into third party ones. It looks like there's all kinds of systems, from custom UHF to Bluetooth LE. No idea what your car uses.