Earlier quoted context omitted.
> the cops say “we pinged your phone”. What that entails exactly I have no clue. The cell phone infrastructure knows where your phone is. It has to in order for it to operate. The police routinely ask cell phone companies for locations of cell phones. Many (most?) not only won't require a warrant, but provide an official portal the police can use to conduct their queries without having to get a phone company employee…
Correct me if I'm wrong, but cell phone companies only know which tower you are currently connected to. So it's pretty inaccurate. The only thing that is "house accurate" is the GPS on your phone. That means they need access to your phone to get that info. Remark that GPS doesn't need to be turned on. Google mapped all Wifi's and so can locate you without GPS.
I was a bit shaken. I believed what you believe before then too.
Edit: Looks like it’s LBS/LCS: https://www.telecomhall.net/t/what-is-lcs-and-lbs/6374