You'll need to remove the door handles to see if the wire that connects to the door handle and the latch is broken.

Hello, very simple.  Take the back panels off of the back doors.  Look for the "hidden" screws behind the little plastic cover tabs on the bottom of the door panels.  the tabs are easily removed by taking a small flat head and popping them off.  Once you have removed the full panel, look for the little plastic nut that guides the lock mechanism,  9/10 it has come loose and will not fully unlock the door.  Simply tighten it back up and your set to go.

Good Luck