hey there junior,
you can try to max reset by removing power from the expedition's sirius receiver for a minute , or remove positive battery cable for a while . since the audio plays ok that rules out possibility of antenna issue.
also if you are nice to the service reps on the other side of the planet I bet they would gladly/specifically enable the ESN for your expedition, as well as sending you a pallet of free sirius stuff like internet wifi radios which they are 'giving away' lately and are very nice little 'wifi radios' indeed. Wifi-radio has "re-sold" me on sirius/XM, for the low low cost of only $3 per month !