Ensure that the default encoding for the browser you are testing is not set to ISO 8859-15.
charset on an a element
Click on the link. Test passes if the two lines on the linked page are the same.
Assertion: A link to a page using the a element with a charset attribute will cause a page with no other encoding information to be rendered using the encoding in the charset attribute.
The target page has no information associated with it that could indicate its character encoding. The text contains the following sequence of bytes: 0xC3 0xBD 0xC3 0xA4 0xC3 0xA8. The characters serve to distinguish ISO 8859-15 from ISO 8859-1, UTF-8 and UTF-16.
The graphic on the lower line of the target page shows what you would expect to see if the page is treated as ISO 8859-15.