Doors lock but won't unlock
 

Hi I'm new here
We have a 2008 Honda Fit in Buenos Aires and the remote locks the car nicely but when I press unlock on the remote, I can hear the unlock noise on the car, but none of the doors actually unlock.
We have to use the key to unlock.
I've disconnected the battery recently for other reasons, but this hasn't helped and I'm very happy to take the car apart if needs must.
Perhaps it's a fuse?
Any ideas anyone?