I have two Motorola devices, a Moto X2 and Moto G3, both with Android M 6.0 (Original most recent ROM without root).
I have recently noticed problems with the GPS on both devices. Google Maps and Waze many times the GPS signal drops and can not determine the location.
In my test I could find that the GPS problem happens when the Mobile Data (only 3G) are active. Just disabling mobile data and GPS back to work with good accuracy and even on rainy days.
I researched on the Internet and can not find a solution to the problem. Already restored the network connections and even restored the factory settings. Also I have been tested to work with modes High Accuracy and Only GPS. The problem persists.
The issue is the same in both devices.