Ajax request doesn't works in Firefox

I was developing a web page but when I try to use it on firefox, i receive an error, the problem is in ajax, when i try to get any information using AJAX I receive "FALSE" in a white screen of firefox, here is the code.

var url = 'aplication/modules/editarData.php';
$.ajax(
{
    type:'POST',
    url:url,
    data:'id='+id,
    success: function(valores)
    {
        var datos = eval(valores);
        $('#cd-name2').val(datos[0]);
        $('#prese2').val(datos[2]);
        $('#clasi2').val(datos[3]);
        $('#quantity2').val(datos[4]);
        $('#distquantityorumos2').val(datos[5]);
        $('#distquantityorumos2a').val(datos[5]);
        $('#distquantityorumitos2').val(datos[6]);
        $('#distquantityorumitos2a').val(datos[6]);
        $('#distquantitydaca2').val(datos[7]);
        $('#distquantitydaca2a').val(datos[7]);
        $('#cd-textarea2').val(datos[8]);
        $("#cd-id").val(datos[9]);
        return false;
    }
});
return false;