if you have an internal battery then I believe you need to change your a-junction out for a ew-90 3 or 5 port in order to work. here is an excellent resource for everything di2:
http://carltonbale.com/...ng-you-need-to-know/
edit: just noticed you said you have external battery. probably firmware update issue then
http://carltonbale.com/...ng-you-need-to-know/
edit: just noticed you said you have external battery. probably firmware update issue then