This is how I replaced the door lock actuator on my 2002 Prius.  I took lots of pictures, so I hope this helps others. 

I purchased the door lock actuator from a Toyota dealer on line for about $85 + $12 shipping, so it was < $100.  Some folks have actually split the old actuator apart and replace the electric motor inside. 

Start by removing the door panel.  This is not hard, but it can be tricky. 

First, push in the center pin of the retainer on the outside edge of the door panel.  This will allow you to easily remove the fastener.

 

This is actually a picture of me installing the fastener, so you can see the pin is pulled out for installation.  However, to remove it you simply push it in and it allows the fastener to be removed.

Here’s a blurry picture of the final installation.

Remove the trim piece in the corner of the window by simply pulling it off.  You can see the location of the fasteners in the photos.

Notice there is a clip at the bottom (hard to see).

There should be a little clip that can easily be removed from under the cover.

 

 

Open the screw cover in the door opening latch handle area.

Remove the screw.

Notice that pull handle trim has a catch that slides into the plastic piece mounted to the door.  It also has “ears” that clip it in place.  This can be somewhat difficult to remove.  If you move the door panel and/or the trim towards the rear of the car, you should be able to slide it out of its latches and hook receptacle.

 

 

 

Remove the screw in the door grab handle recess.

You should be able to remove the entire switch assembly. 

Note the fastener on the front of the switch assembly.  This should pull straight up.

 

Now you can start unclipping the door panel.  Note that I used my hands and some plastic pry tools…you don’t want to scratch things up. 

Note the location of the clips.

 

 

 

 

Hopefully you can lift the door panel up and off the door by this point.  I had some difficulty with the door pull handle trim, but be patient and don’t break it!

Now remove the metal bracket.

 

 

You should be able to peel the plastic away and expose the cover.  Remove three screws.

Remove the cables from the clip.

Now we’re going to remove the entire latch assembly from inside the door with the lock actuator attached.

There are actuator two rods that have plastic clips.  You simply push up on the plastic clip to unlock it from the rod and then you can remove the rod from its hole.

 

Remove the torx fasteners that hold the door latch in place.

Remove the bracket bolt.

If you remove these nuts, you can swing the window rail track out of the way so the latch and actuator assembly can easily be removed.

 

As you remove the latch assembly, you should be able to unclip the electrical connector from the actuator.  Greasy and sweaty…

Now you can remove it from the top hole.

Remove the plastic cover by removing this screw.

Pull the cover off exposing cables

Remove the two attaching screws.

You should now be able to remove the cable and the ball/socket lever.  Note how it fits together while you are removing it.  It’s pretty simple, but make sure you get everything oriented the correct way when installing.

Old and new.

Now see if you can do it all backwards to install it.

Testing, 1…2…3.