The test is as follows:

(:*******************************************************:)
(: Test: K2-SeqDocFunc-9                                 :)
(: Written by: Frans Englich                             :)
(: Date: 2007-11-22T11:31:21+01:00                       :)
(: Purpose: A windows file path is an invalid URI to fn:doc()(#3). :)
(:*******************************************************:)
doc("C:\example.com\example.org\does\not\exist\doesNotExist\works-mod.xml")

If the URI is not interpreted as a valid document URI, then the error should be FODC0005.

This can be interpreted as a valid URI (the '\'s can be % normalized, and the URI is in the 'C' scheme).  In the unlikely event that an implementation does provide a mapping for the 'C' scheme, this could be an FODC0002 error, although I would argue that this case is so obscure that it should not really be considered a valid result by XQTS.