Woocommerce – Attribute Archive page

I’m trying to implement the following:

http://wcdocs.woothemes.com/codex/extending/using-custom-attributes-in-menus/

I put this code into functions.php:

add_filter(‘woocommerce_attribute_show_in_nav_menus’, ‘wc_reg_for_menus’, 1, 2);

function wc_reg_for_menus( $register, $name = ” ) {
if ( $name == ‘pa_brand’ ) $register = true;
return $register;
}

After I copyed the taxonomy-product_cat.php into my theme folder and renaimed it taxonomy-pa_brand.php

The attributes show up into the menu, but when I click them it shows a white page.

The link on the top is http://www.sitename.com/brand/nameofthe brand

How can I make it work? to show the products?