It is just a wear and tear item.
Scion door lock issues.
It is time to bring it in for repair.
All doors multiple doors fail to lock unlock.
All doors multiple doors fail to lock unlock.
For the fuse there is a door window fuse in the fuse box.
The door actuator going bad is a pretty common maintenance item with cars.
Apdty 136028 front left driver side door lock actuator fits 2004 2006 scion xb 2000 2005 toyota echo replaces 6912052030 69120 52030 4 5 out of 5 stars 6 14 90.
The 2006 scion xb has 7 nhtsa complaints for the latches locks linkages at 67 215 miles average.
If you have multiple doors or all doors failing to lock unlock with the key fob and the interior door locks it is most likely a larger electrical issue.
If you have multiple doors or all the doors failing to lock unlock you either have a simple blown fuse or a much larger wiring issue.