The 911 feature can be activated fully remotely, the 112 feature is supposed to only activate when dialing an emergency number.
Source? Even if the phone isn't actively doing a 911 call?
>The dispatcher's computer receives information from the telephone company about the physical address (for landlines) or geographic coordinates (for wireless) of the caller.
Unfortunately, definitive capabilities and constraints of this kind of cellular technology is hard to come by.
The format is not secret either, it's just binary encoded.
The spec says:
> The AML SMS should not be seen by the caller and therefore should not appear in the SMS "sentbox" of the smartphone. This is to avoid any customer confusion and to avoid making the format of the message widely known. In addition, there is also a potential privacy concern in storing the location of an emergency call from the handset, which could be seen by others.
The AML SMS gets triggered by software on your smartphone when you dial an emergency number. You cannot use it to obtain someone else's location.