process-navigations.ts

this.configLoader = new RouterConfigLoader(loader, compiler, onLoadStart, onLoadEnd);
this.processNavigations();

processNavigations(): void {
    this.navigations.pipe(concatMap((nav: NavigationParams) => {
        if (nav) {
            this.executeScheduledNavigation(nav);
            // a failed navigation should not stop the router from processing
            // further navigations => the catch
            return nav.promise.catch(() => {});
        } else {
            return <any>of (null);
        }
    })).subscribe(() => {});
}