When you activate the GPS, it will use it to determine your location and when you are out of the GPS signal (for e.g. inside a building), then after 10 seconds the Wi-Fi takes over.
With the Wi-Fi, the scan's activated SVC+ sometimes performs brief Wi-Fi scans (even if the Wi-Fi is turned off) to determine your location accurately. Although it seems counterintuitive, these Wi-Fi scans significantly improve the location accuracy and battery life. With Wi-Fi scans, the location accuracy is typically within 100 meters.
When you are even out of the Wi-Fi signal, then the location is determinated by the GSM network, which has an accuracy of within 2,000 meters. In this case, we suggest you add more circles (place radius) arround your desired location just to be certain your phone will correctly locate you.