Hi, has anyone else had this problem? It's the rear driver's side door, the door lock button seems stuck. It's a rocker switch and seems stuck in the middle. So will not fully lock or unlock. These door locks are manual. Most write-ups are for power locks. Thanks in advance for any help! Do I have to take the entire door panel off?

 

Although I have no experience with the rear door, I know on the front doors you can pull the window felt up and access the door latch mechanism with a coat hanger to pop the door open. See if that can work for the rear door.

And if you're like me and stuck 2000 miles from home and your wife accidentally locks your keys in the car, you can use the antenna as the coat hanger.

 

The part of the door button/ handle that the lock / unlock mechanism moves is rusted or gunked..if the door will not open get some penetrant oil with the thin red spray tube and push the tube in between the window and the seal on both sides where the push button is and spray an inch in either direction. If you wait overnight the lock mechanism will probably work. If the door opens there is a oval rubber plug above the latch that accesses the same area

 

I know for a fact that you can get the rear door panel off in a '97 and up with the door closed.
But pretty sure I had to pull out the bottom of the back seat when I did it.

 

Absolutely this!

Remove the bottom of your rear seat, remove the 3 Phillips head screws that retain the door panel to the door (one around the door handle and then should be 2 bigger ones in the armrest area.

The panel is a little tricky to get free but stay motivated in removing it from the bottom first, then when you get the panel free lift it up and away to remove it. The top of the panel has an edge that tucks into the window seal kinda like a candy-cane for simple example. Once it's popped free you can detach the 2 rods which actuate the door lock mechanism and then the door latch itself.

I wouldnt bother trying to manipulate the rods while still attached to the panel, it'll be much easier to do this with the free and you will also have more leverage.

now you can lubricate the latch from one of the multiple acces hole sin the door and then slowly work at the rods until its functioning properly

 

Like they said, the door panels are removable from the inside. It isn't as easy as when the doors are open but it's definitely do-able.
I went a couple steps further by taking out the latch mechanism and washing out the old grease and gunk then re lubing it and the linkages.

Since "troubles come not in single spies but in battalions" I did the other three doors to save some hassle. Then flushed the hood latch cable with teflon.