Since I was a kid, eagerly scrutinizing cars in parking lots, I remember noticing something that only showed up on a few brands of cars: Fords, Lincolns, and the occasional Mercury. That something was a set of five little buttons, each bearing a pair of numbers, placed near the doorhandles of these cars and looking so very tempting to push with my curious little kid-fingers. To this day I don’t believe I’ve ever actually seen anyone use them, and the more I think about them, the stranger they seem. Why does only Ford use these? What, exactly, are they for? I finally found out, and they’re shockingly simple and smart. Which brings up a bigger question. Let’s dig in.

I think I’ve not been clear on what these were for for so long because the only Ford I’ve owned recent enough to possibly have them— and recent here is generous, since the buttons have been around since 1980—was the That one never had the numbered keys, and if it did, we would have just torn them out, anyway.

Those sets of keys were first introduced as an option for the , Mark IV, and . They were initially called the “Keyless Entry System,” but as radio-operated remote-unlocking key fobs became more and more common, a new official name was registered for them in 2009: Securicode.

At its simplest, Securicode is just a combination lock for a car. Really, that’s pretty much it! Here’s how it was described (back when it was still the Keyless Entry System) on its introduction in 1980, from a Lincoln press release:

The press release says:

“The Keyless Entry System permits door locking, door unlocking and decklid release from outside the driver’s door without a key. The complete system consists of a row of five push buttons on the driver’s-door belt molding that are connected to a minicomputer.

The push buttons are back-lit for nighttime use and are similar to those used on small calculators. To unlock the driver’s door, one simply pushes the buttons in a pre-programmed five-digit sequence. By pressing specific buttons, the driver also can unlock the rest of the doors, lock all the doors or release the decklid.”

I really like the terminology of calling the crude late-’70s-era mass of integrated circuits and resistors in there a “minicomputer,” and when they say the keys were like calculator keys, that’s accurate—I think they had the same viscerally pleasing rubbery squishiness of some calculators of the era.

It’s interesting Ford chose to go with just five keys yet use the full set of 0-9 digits; while electronically, it’s just a five-digit code made of five possible digits () by using the full set of numbers people could set their own codes with, say, most of the digits of their birthday. (You’d need six digits if you were born in the last three months of the year.)

I haven’t been able to confirm this, but I suspect that was a limit of the computer hardware at the time, especially in an era when memory was very expensive—five digits is half the amount of data to store than 10, after all.

So, with this system you could do some simple but important tasks: unlock the car, unlock all doors (press 3•4 within five seconds after your code), open the trunk (press 5•6), or lock all the doors (press and hold 7•8 and 9•0 at the same time with the driver door closed).

Now, if you’re thinking what’s the big deal about this? I still need a key to drive the car, anyway, then you’re not thinking big enough, friend.

These little buttons mean that you can never get locked out of your car! If you know your code, there’s no expensive, day-ruining penalty for accidentally leaving your keys in the trunk or whatever. This is a big deal, and if a powerful yet little known locksmiths’ lobby exists, could explain why Securicode hasn’t become universal.

It also lets you choose to lock your keys in your car, which is really a nice option to have. For example, on the car in a Very Secret Spot, because I know that taking the keys to the car in the canoe with me is just a recipe for a few moments of panic as they plop overboard out of a poorly-engineered pocket and then a miserable evening as I wish, hard, I had a time machine.

If I had an unlocking keypad on the door, this would be no problem at all.

There’s all kinds of situations like these when you think about it—you could leave a pet in a car in the summer for a 10-minute hop into a store if you could lock the car and still keep it idling with the A/C on and everyone nice and comfy, or alternately, in the winter with the heater on. This little keypad could make that possible.

Also, if you ever have a day go so badly that you wake up, cold, naked, maybe bleeding a little, and you’ve lost you wallet and everything, if you can at least crawl your way back to your car, you could still get in, cover yourself in floormats, cry and recover.

It’s just a simple, clever, convenient thing, and I think now I understand why I’ve never seen one in use—because I think these things are more likely to be used in remote places, where you wouldn’t want your keys on you, like out hiking or camping or sneaking into some mysterious rich-guy sex cult party or something like that.

Ford has offered the Securicode on almost everything they make, and when it’s not standard, it’s a cheap option, usually around $50.

Modern versions of it have gone away from the little keys and are now capacitive-touch buttons hidden in the door pillar:

I’m not trying to be a big Ford shill here, but I have to say that I’m surprised no other automaker has decided to copy this! It seems pretty cheap to implement and useful—just the part about never worrying about getting locked out of your car seems good enough, since you can still manage to do that even with modern electric key fobs, if you’re committed enough.

Other similar simple convenience features like the kick-to-open-the-tailgate spread throughout the industry in just a couple of years—why hasn’t anyone else added a similar system to their cars?

It’s not like the engineering is especially complex, and I’m pretty sure any carmaker’s lawyers can argue that combination locks for cars aren’t really protectable enough to enforce exclusivity. My only guess is that other automakers don’t really care.

Again, Ford’s not paying me, and I don’t care if you never buy a Ford in your life, but I’m going to call out a good idea when I see one, and, I have to say, these goofy little buttons are a good idea.

They seem to be popular among Ford owners, who seem to treat it as a bit of an in-group secret? Feels like some carmaker needs to horn in on this territory already, right? I’m sure the temptation would be to make it more complex, like fingerprint scanners or facial recognition, but I think a simple keypad still makes the most sense.

Are there Ford/Lincoln/Mercury owners out there who have used this and can tell us why it’s great, or you don’t care, or a time it saved your ass? I’m really curious.

Clever, clever readers have reminded me that, briefly, Nissan Maximas had door keypads, too! Look!

Interestingly, they kept with the dual number per button method.

Also, for some vehicles:

Again, we’ve got two numbers per button on a five-button keypad. Still, Ford is by far the biggest proponent of these.