Re: Important: How to turn off E911 tracking chip on the LG V20
McAffee is 100% full of crack.
First, there is no "E911 chip" in the phone. Second, the RIL (that's the software layer that talks to the cellular system) has had a callback interface for a VERY long time (first device I had that caused me trouble with it was the T-Mobile Valiant, if you remember that one) -- and it's basically undocumented since the RIL is closed-source.
When I ran into the problem the issue was that when the RIL sent the request if you didn't answer it "as it wanted" it would not open the VOICE channel! This meant if you dialed 911 with a custom ROM the operator could not hear you, but you could hear THEM. That in turn freaked them out BIGTIME as they assumed you dialed as you were bring shot, etc. VERY VERY BAD.
These broadcasts are typically handled by the "cell broadcast" service manager, which is sort of the same deal but NOT the same as E911's callback interface. These alerts are a multicast transmission, basically; the network sends the last index number for each category so it's not sending the actual alert repeatedly, but as long as it's valid if your device is turned on you'll get it (exactly once.) This covers the instance where you're in a tunnel (for instance) when the alert goes out but then 2 minutes later emerge from same; you'll still get it. You CAN remove the listener if you want in which case the callback will go unanswered but the last time I looked (which was admittedly a while ago) it had no transmission capacity to send back something like your GPS coordinates -- nor would it make sense to do so, as those broadcasts are typically used for very wide-area things (e.g. hurricane or flood warnings) and would result in an avalanche of responses.
Shut it off if you wish but no, the President isn't going to be getting your cell's location from that. If they want it they'll ask the network to trace your node which will give them decent resolution without it anyway since from the network management system it can (using time-domain analysis) get a pretty-accurate read using nothing more than the routine network management interface on THEIR end, and which you can't shut off (other than by turning off the device entirely.)
BTW this mechanism built into the cell system is QUITE useful in that the NWS uses it for tornado warnings and similar, and they can be targeted to the individual cell level. As such if you get a tornado warning or similar alert on your cell you can be reasonably sure that it really means it and is local to where you are at that moment in time.