If we were to talk about today's greatest automotive features, I think we could all agree that two really stand out above the rest: a roof-mounted rocket launcher and Ford's keypad entry system.

Ford is about to mark 40 years of offering one of the auto industry’s least known but most appreciated features: the SecuriCode keypad. Millions of Ford and Lincoln owners have used the feature.

Since the 1980s, many vehicles produced in the Ford family have come with a five-button keypad that can be used for unlocking them in place of the physical key. Other automakers have implemented the ...