My mistake

HTML

<div ng-controller="myCtrl">
			<select ng-change="changeCity()" name="make" class="form-control" ng-model="selectCity">
    <option value="Kannur">Kannur</option>
    <option value="Agra">Agra</option>
    <option value="Ahemedabad">Ahemedabad</option>
    <option value="Bangalore">Bangalore</option>
    <option value="Chennai">Chennai</option>
    <option value="Mumbai">Mumbai</option>
</select>
</div>

JavaScript

var app = angular.module('myApp', []);
app.factory('APIservices', function($http){
    var APIcarModels = {};
    APIcarModels.getAPIcarModels = function(arg){
        alert(arg);
       // return $http.get('/carprices3/api/apiData'+ selectCity +'.js')
    }
    return APIcarModels;

});
function myCtrl($scope,APIservices) {
    $scope.changeCity = function(){
    APIservices.getAPIcarModels($scope.selectCity);
    };
   
}