[ammar2]

> Unless E911 works by transmitting your devices' GPS readings from its own hardware to authorities

That's exactly how it works:

> When the cellular phone detects that the user is placing an emergency call, it begins to transmit its location to a secure server, from which the [Public Safety Answering Point] can retrieve it. Cellphone manufacturers may program the phone to automatically enable GPS functionality (if disabled) when an emergency call is placed, so that it may transmit its location.

https://en.wikipedia.org/wiki/Enhanced_9-1-1#Wireless_transm...