GT,
If the lock cylinder will not turn with the key in it it is most likely corroded. Spray in some penetrating oil, like WD-40 or JB Blaster and let it soak in for a day or two.
If that does not free up the cylinder it will have to be replaced. Before you do that, does your pasanger side door lock cylinder work (if you have a right side cylinder)? You could swap the right side to the left door it it works.
If you buy a new cylinder you should have it set to match your key.
If you are pulling up on the door handle and it is not opening the door, then the connecting rod between the handle and the latch may be out of adjustment, or your lock cylinder and its connecting rod is stuck in a position that will not allow the handle to open the latch. That is how the lock system works.
You need to get a look inside the door to determine what is going on inside. There are several rod links that could be out of adjustment, or could have become disconnected.
Once you get your locks working, they should be lubricated with a silicone spray lubricant a couple of times a year. It is also a good idea to use the key to unlock the doors a couple of times a moth to keep thins working, especially the drivers door and the trunk IMHO.
Let us know if you need information on getting the door panel off, if you have never done this before.
rangerj
