94 Park Avenue door lock problem

I can lock the driver door with the power lock switch inside but I cannot unlock the driver door with the unlock switch. I can unlock the other doors with the unlock switch. To unlock the driver door I must manually lift the lock lever. Also, when the driver door is locked, I cannot unlock it from outside with a key. Any ideas what the problem is?

Welcome to AF! You have a problem with the lock mechanism inside the door frame. The inside panel will need to be removed to expose the problem. Typically, a plastic clip on the actuator rod will cause this problem. This is a common on the 94-95 models.

Ok. Who would be a best choice to fix this, my regular mechanic or a body shop?

Most mechanics and glass replacement shops can remove the door panel. The ones who have been around for awhile, in all probability have already repaired the same problem as you have.