•When your GPS antenna is covered (for example, by your hand or other object) or facing the ground
•In temperature extremes outside the operating limits of your phone
Walking or driving very slowly may also substantially reduce GPS performance.
Even where location information can be calculated in such situations, it may take much longer to do so, and your location estimate may not be as accurate. Therefore, in any 911 call, always report the location to the emergency response center if you can and if you cannot, remain on your phone for as long as the emergency response center instructs you.
Even where adequate signals from multiple satellites are available, your GPS feature will only provide an approximate location, often within 150 feet (45 meters) but sometimes much further from your actual location. Advice on how to improve GPS performance is provided in “Enhancing GPS Performance” on page 75.
While the GPS feature of your phone can be a valuable navigational aid, it does not replace the need for careful navigating and good judgment.
Never rely solely on one device for navigation.
Remember that the accuracy of the location
Making an Emergency Call
information and the time needed to obtain it will vary depending on circumstances, particularly the ability to receive signals from adequate numbers of satellites.
On emergency calls, your phone uses assistance information from the phone network to improve the speed and accuracy of your phone’s location calculation: if such assistance information becomes unavailable, it may reduce the speed and accuracy of the location calculation.
The satellites used by the GPS feature of your phone are controlled by the U.S. government and are subject to changes implemented in accordance with the Department of Defense GPS user policy and the Federal Radionavigation Plan. These changes may affect the performance of the GPS feature of your phone.
Making an Emergency Call
Dial 911 to be connected to an emergency response center. If you are on an active call, you must end it before calling 911.
When you make an emergency 911 call, the GPS feature of your phone begins to seek information to calculate your approximate location. It will take the GPS feature of your phone some time to determine your approximate location. Even where your phone has good access to sufficient
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