Hi mw.
Corydoras is correct in what he said, see page 232 of the 5DIV (UK English) manual.
Also note the advice on how to acquire the GPS signal. Bear in mind that for the first time or after a large distance has been travelled from the last GPS location it can take significantly longer to acquire a lock. Standing still 2 or 3 minutes, if I turn GPS on before walking from the road in to the local hide it can take 5 or more minutes, yes it seems walking speed can make it harder to acquire a lock, and yes I carry the camera the right way up until it has a GPS lock then let it hang on the BR strap as normal, I have to do that as it pretty much won't acquire a lock inverted however long it tries, but it can maintain a lock when carried inverted, it also seems to be able to maintain a GPS lock in moderate foliage cover, or perhaps it just fakes it somehow.
Cheers, Graham.