Door Lock Switch Test
WARNING: This page is about a different car, the 1997 Mercury Sable and 1997 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.
Remove door lock switch. Measure resistance between switch terminals. With switch in neutral position, resistance should be 25 k/ohms or greater. With switch in unlock position, resistance should be less than 200 ohms. Replace switch if resistance is not within specification.