Battery in good condition? I found when my original battery was on its last legs I didn’t seem to get heated mirrors or rear screen defrost when very cold, same with stop start. New batt and a few runs and it was ok, also had a prod at a few of the relays behind the fuse box not sure which of those worked but the combo did. Relay may have worked it’s way out i pushed one in a few millimetres that had worked out.