Have an ls430 and the rear driver side door lock lever moves freely back and forth but does not lock or unlock manually. It's as if it became unhooked or something. Any thoughts what it may be and is it a pain to disassemble the door lock area to,take a look? What is also happening is the doors are not unlocking when I put the car in park. Wasn't sure if this may be a byproduct of the lock lever being disengaged.

 

It is not too bad of a DIY project. Take a look at Step 5c in the drawings below, one of the cabls is either unhooked or broken.

Regarding unlocking all 4 doors when you put the car in park, this is a user-configurable function.