Jquery Error

Hy I have problem with ajax, can’t get value from json always get massage from console
xhr.send( ( options.hasContent && options.data ) || null );

On what is concern this error.
This is Query code

$(document).ready(function(){
 function refreshSmallBasket(){
        $.ajax({
             type: 'POST',
            url:'mod/basket_small_refresh.php',
            dataType:'json',
            success: function(data){
                $.each(data, function(k, v){
                    $("#basket_left ." + k + " span").text(v);
                });
            },
            error: function(data){
                console.log(data.status + " " + data.statusText);
            }
        });
    }

//if there class with name add_to_basket
    if($(".add_to_basket").length > 0){
        //on this class on click execute
        $(".add_to_basket").click(function(){
            //this click with this class
            var trigger = $(this);
            //add attribute rel from link
            var param = trigger.attr("rel");
            //split atribute with _ example rel= 2_3 we spleet 2 and 3
            var item = param.split("_");
            
            $.ajax({
                type: 'POST',
                url:'mod/basket.php',
                dataType: 'json',
                data: ({ id : item[0], job : item[1]}),
                success: function(data){
                    var new_id = item[0] + '_' + data.job;
                    if(data.job !=item[1]){
                        if(data.job == 0){
                           trigger.attr("rel", new_id); 
                            trigger.text("Remove From Basket");
                            trigger.addClass("red");
                        }
                        else{
                            trigger.attr("rel", new_id);
                            trigger.text("Add To Basket");
                            trigger.removeClass("red");
                        }
                        
                        refreshSmallBasket();
                    }
                },
                error:function(data){
                    console.log(data.status + " " + data.statusText);
                }
            });
            return false;
        });
    }

});

If you check the jQuery manual page for the $.ajax function, it says that the error callback takes three arguments: The jqXHR (request) object, a string describing the type of error, and a string with actual error message that was returned.

Try changing your functions to output the 2nd and 3rd arguments to the console to get more useful information about the error.