Are you talking about the key not working in the door locks, or the locks don't lock or unlock when you lock or unlock the drivers door. If it's the key, you probably just have a bunch of pocket lint in the locks. The happened to my wagon. You have to pull the handle out and clean the barrel of the lock. If it's the later you have vacuum leaks. Which you'll need a mity-vac to figure out which one(s) are leaking.

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