Lock Switch Testing
WARNING: This page is about a different car, the 1997 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.
Remove 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.