I have inherited a switch with the following vlan access-map configuration:
vlan access-map vlan 12
No corresponding ACL anywhere else in the configuration.
Do these statements actually do anything? Additionally, exactly what does the command "vlan access-map" do?
No i don't believe from what you have said that they do anything. For one thing there are no match clauses in the vlan map.
Do you know if this map has actually been applied to a vlan ie. is there a line in your config that begins "vlan filter ....".
vlan maps are used to filter traffic within a vlan ie not via a routed interface. You can match on mac-address or IP address.