AJAX test module is not working. POST 404 error

Question

I'm trying to create my own ajax module. When I submit the form I'm getting a 404 post error. Any idea what went wrong?

This is what I have done so far.

mod_ajax_test.xml

<?xml version="1.0" encoding="utf-8"?>
<extension type="module"
           version="3.0"
           method="upgrade">
    <name>Ajax Test</name>
    <creationDate>February 7, 2017</creationDate>
    <author>Striker8472</author>
    <authorUrl>http://doa-x.com</authorUrl>
    <copyright>Copyright (C) 2017 doa-x.com. All rights reserved.</copyright>
    <license>GNU General Public License version 2, or later.</license>
    <version>0.0.1</version>
    <description>Ajax Test</description>
    <files>
        <filename module="mod_ajax_test">mod_ajax_test.php</filename>
        <filename>helper.php</filename>
        <folder>tmpl</folder>
    </files>
</extension>

mod_ajax_text.php

<?php defined('_JEXEC') or die;

/**
 * File       mod_ajax_test.php
 * Created    2/7/17 17:12 PM
 */

// Include the helper.
require_once __DIR__ . '/helper.php';

// Instantiate global document object
$doc = JFactory::getDocument();

$js = <<<JS
(function ($) {
    $(document).on('click', 'input[type=submit]', function () {
        var value   = $('input[name=data]').val(),
            request = {
                    'option' : 'com_ajax',
                    'module' : 'mod_ajax_test',
                    'data'   : value,
                    'format' : 'raw'
                };
        $.ajax({
            type   : 'POST',
            data   : request,
            success: function (response) {
                $('.status').html(response);
            }
        });
        return false;
    });
})(jQuery)
JS;

$doc->addScriptDeclaration($js);

require JModuleHelper::getLayoutPath('mod_ajax_test');

helper.php

<?php defined('_JEXEC') or die;

/**
 * File       helper.php
 * Created    2/7/17 17:12 PM
 */
class modAjaxTestHelper
{
    public static function getAjax()
    {
        $input = JFactory::getApplication()->input;
        $data  = $input->get('data');

        return 'Your text here: ' . $data . '!';
    }
}

tmpl/default.php

<?php defined('_JEXEC') or die;

/**
 * File       default.php
 * Created    2/7/17 17:12 PM
 */

?>
<form>
    <input type="text" name="data">
    <input type="submit" />
</form>
<div class="status"></div>

Answer 1

Found the problem by myself.

'module' : 'mod_ajax_test',

must be

'module' : 'ajax_test',