I see no brand logo at the product page. How do I fix this?

If you don't see the brand logo on the product page when using the Improved Layered Navigation please make sure:

1) Magento attribute "manufacturer" has property `Visible on Product View Page on Front-end` set to "Yes"
2) The module filter "Manufacturer" has option "Show on Product" set to "Yes"
3) The code ...showLinks($_product)...  is added to the right template (some extensions like EasyTabs changes the product view template), enable template hints to check.