Why is my pathfinder 2002 always running down my batteries down?

For over a year now, my pathfinder 2002 has been running batteries down once you pack it down for maybe over 6 hours without moving it around.

Again, the central lock stopped working once the ignition is off. It can only work while the ignition is on or the car's engine is running. Again, I also noted that the car central timer is not working again. Please help me out.