I have a 2002 Rav4 4cyl with 165,000 miles. Automatic trans. AWD. 

I went to open the drivers door with the key and turned it twice to open all doors. It made no noise but only opened the drivers door. All others remained locked. When I got in the car, I pushed the auto “unlock” button on the drivers door and it would not unlock the other doors. If I push the auto “lock” button on the drivers door it will lock all the doors. I got out of the car and used the key in the drivers door and it locked all the doors. Also, as I was driving, every so often I could hear a noise as if the car was trying to lock/unlock the doors. I can also lock and unlock the doors manually by using the lock stems on the top of each door.

Thanks!