code: public void setOverwritingStatus(boolean enabled) {
          mOverwriteNativeStatus = enabled;
          mNativeGpsOverridden = false;
          if(mLocationManager != null && !enabled) {
              try {
                  mLocationManager.removeTestProvider(
                          LocationManager.GPS_PROVIDER);
                  Log.d(TAG, "Disabled overwriting native GPS with OpenXC GPS");
              } catch(IllegalArgumentException e) {
                  Log.d(TAG, "Unable to remove GPS test provider - " +
                          "probably wasn't added yet");
              }
  
              mVehicleManager.removeListener(Latitude.class, this);
              mVehicleManager.removeListener(Longitude.class, this);
              mVehicleManager.removeListener(VehicleSpeed.class, this);
          } else {
              Log.d(TAG, "Enabled overwriting native GPS with OpenXC GPS");
  
              mVehicleManager.addListener(Latitude.class, this);
              mVehicleManager.addListener(Longitude.class, this);
              mVehicleManager.addListener(VehicleSpeed.class, this);
          }
      }
docs: Enable or disable overwriting Android's native GPS values with those from
  the vehicle.
  
  If enabled, the GPS_PROVIDER from Android will respond with data taken
  from the vehicle interface. The native GPS values will be used until GPS
  data is actually received from the vehicle, so if the specific car you're
  plugged into doesn't have GPS then the values will not be overwritten,
  regardless of this setting.