Q&A

 Master

You are doing exactly what I would do. I would remove the driver's door inner panel, put the window fully up look at the lock mechanism and linkages and with the lock unlocked maneuver the lock linkages to open the door.
Perhaps it would help if you took the passenger door panel off and looked at the extent of travel the linkage has to have to "open the latching/lock mechanism. The springs in the lock must have failed. I have not have to replace the locking mechanism too often on Toyotas.

 Rookie

This is probably a broken spring on the door latch. There are step by step instructions with photos posted somewhere. Do a Google search something along the lines of "previa stuck door lock spring repair". Expect to spend a couple hours and do lots of cussing. It is an easy and cheap DIY repair, but like everything on a Previa (in my experience), it will not inspire you to send a fan letter to the Previa design Engineers.

Contrary to what others may say, I find this a medium-hard repair.

I've fixed my Previa driver-side door twice for this very problem. It has been a broken tension-spring each time. I simply use a similar spring from my spring collection (boxes of assorted tension springs are available at most hardware stores). The real challenge is to get the old broken spring out and the new one in.

You'll have to remove the inside door cover and the protective plastic sheet to get to the lock mechanism. Look over to the left with a flashlight. Also, it's often useful to lower the window and look in from the top of the door. I find a hemostat the most useful tool to position and tension the new spring, but needle-nose pliers or small vice-grip pliers might do as well.

You might not know where the new spring goes, because the old one has broken and fallen off. If you can't figure this out, undo the passenger-side door as you did with the driver-side to see where the spring should go. Be patient! You can do it.