Comment by drnick1

As far as I know, all modern Toyotas have discrete DCMs (data communication modules) that can be physically unplugged with limited side effects. The side effects are loss a speaker and hands-free microphone, but they be restored by means of a bypass harness. Simply unplugging the antennas does not seem to be enough in areas with good cellular coverage. I have seen the dummy load approach discussed on car forums but have no experience with it.