allowDeferredLocationsUpdates在模拟器上工作但不在我的iPhone 6s上工作

Question

我试图了解deferredLocations功能。根据苹果文档，以下应该可以正常工作，当我在模拟器上运行时，它就会运行，但是一旦我在iPhone 6s上安装应用程序并断开iPhone并运行应用程序，位置更新就不会被推迟。我正在使用XCode 8和swift 3。

以下是代码：

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    locationManager=CLLocationManager()
    locationManager!.delegate=self

    locationManager!.desiredAccuracy=kCLLocationAccuracyBest
    locationManager!.requestAlwaysAuthorization()
    locationManager!.distanceFilter=kCLDistanceFilterNone
    locationManager!.allowsBackgroundLocationUpdates=true
    locationManager!.pausesLocationUpdatesAutomatically=false
    locationManager!.startUpdatingLocation()

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    if (!self.deferringUpdates)
    {
        locationManager!.allowDeferredLocationUpdates(untilTraveled: CLLocationDistanceMax, timeout: 60)
        self.deferringUpdates=true
    }
}

func locationManager(_ manager: CLLocationManager, didFinishDeferredUpdatesWithError error: Error?) {
    i=i+1
    label.text="\(i)"
    print("didFinishDeferredUpdatesWithError")
    locationManager!.disallowDeferredLocationUpdates()
    self.deferringUpdates=false
}

我得到错误代码= 11，这是根据苹果文档不可用的GPS或类似内容。