Smartphones Replace Fobs for Keyless Vehicle Entry

Lincoln and Amazon are the latest companies to harness smartphone apps for easy vehicle entry

Photograph of a Lincoln Aviator in the background with a hand holding the Phone as Key app open on a smartphone.
Photo: Ford
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Roll-up windows. Cigarette lighters. Physical ignition keys. All of these features have gone virtually extinct in modern automobiles. The quaint metal key gave way to transponder fobs, which led to “proximity keys” that don’t leave your pocket at all. Now, smartphones are becoming the new gatekeepers, as car companies roll out features that let drivers unlock and start their cars through an app.

Volvo began offering its subscription-based On Call service in 2016; it allows owners to use the company’s smartphone app to lock, unlock, and start their cars. With it, users can also remotely check vehicle fuel levels, receive service alerts, or send destinations to the onboard navigation system.

Tesla, which has never been shy about beta testing on its customers, then attempted to sell a car with no fob at all: The Model 3 sedan was initially available with only smartphone-based entry and ignition, and a backup RFID card. Beset by customer complaints of spotty operation, Tesla began offering a familiar fob last fall for an extra US $150. Yet that fob didn’t allow the “passive entry” of the smartphone system, requiring owners to push a button to enter or lock the car. 

Now it’s Lincoln’s turn. Ford’s luxury division will bring two SUVs to market this year, the midsize 2020 Aviator and compact 2020 Corsair. Traditionalists will still receive a standard fob, but adventurous types can pay extra for the Lincoln’s app-based, optional “Phone as a Key” system. 

The Lincolns use a Bluetooth Low Energy (BLE) connection to link smartphones to SUVs. BLE is a short-range communication system that sacrifices high data speeds for long battery life. As with a proximity key, the Lincolns recognize a linked phone, then unlock when you touch the door handle, and start via pushbutton when the phone is physically inside the car. Walk away from the vehicle, and it automatically locks.

The upside is obvious to anyone who’s fumbled in a purse for a set of keys, or fretted over how much stuff ends up crammed into their cargo pants: Since you’re carrying a smartphone anyway, why carry a clunky fob too? Especially when the app can do even more.

Within a roughly 40-meter range, Lincoln owners can remotely start and warm up their cars, raise the liftgates, or open and close windows. Phones link to a BLE module inside the car, with a logic processor and sensors that locate the phone through triangulation. Up to four users can share a virtual key across their Apple or Android smartphones. Each of them can create profiles that automatically prep the Lincoln to their tastes, with up to 80 presets for seats, climate control, audio system, mirrors, and the steering column.

Of course, for any new tech, the promise of convenience goes hand-in-hand with unforeseen consequences: When key fobs with pushbutton ignitions arrived, owners would regularly walk away from running cars with the fobs still in their pockets—after handing the cars off to valets, or switching places with a passenger after driving to work or the airport. When the valet or new driver shut off the car, it couldn’t be started again until the key was tracked down.

Brian Wilkerson, product manager for Phone as a Key, said the system’s developers took pains to identify and solve potential hiccups, including an obvious one: “If the phone died, or you had Bluetooth problems, we had to have backup capability,” Wilkerson says.

Like many Ford and Lincoln models, the Aviator and Corsair integrate flush-mounted, numeric touchpads on their driver’s side roof pillars. If a phone is dead, or there’s no cellular connection, owners simply punch in any entry code, followed by a code in the interior touchscreen to start the engine. For valets or other temporary users, the app will generate a one-time entry code. The new Lincolns also integrate wireless charging pads, reducing the chance that a driver’s device will run out of juice.

Security is safeguarded through the familiar passwords, fingerprints, and other authenticators used on any smartphone screen. If the phone is lost, the app can quickly be deleted.

Code-based, cellular-linked technology seems to have also inspired Amazon. Its Amazon Key allows employees to leave packages in customers’ vehicles if they drive 2015-and-newer models from Volvo and General Motors’ Chevrolet, Buick, Cadillac, and GMC divisions. And on 30 April, Amazon announced it would expand its delivery service—now available in 50 U.S cities—to all 2017-and-newer Fords and Lincolns that offer cloud-based connections to its Lincoln Way and FordPass apps (which offer the Phone as a Key feature). Link an Amazon Prime account to a Ford or Lincoln, send a secure entry code, and the e-commerce giant will securely drop your new Instant Pot, wireless earbuds, or Game of Thrones Monopoly board in your car.

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