The story sounds like an automotive industry urban legend: You use your Ford Explorer's remote keyless-entry fob to open the doors, and the trunk on a nearby Lincoln pops open, exposing golf clubs and other goodies.
Yet it did happen in Maumee - and could happen with other cars and trucks, too.
Still, the chances probably are one in billions with late-model vehicles, even as more cars and trucks are equipped with radio-frequency-controlled keyless entries, automaker and supplier officials said.
“From our experience, we think it is highly, highly uncommon,” said Tom Gioia, manager of electrical architecture and safety technologies at Visteon Corp., which made the Explorer's keyless-entry system and possibly the one on the Lincoln.
No one at Ford Motor Co. was available to comment this week about the Maumee incident involving two of its vehicles.
Other automakers and parts suppliers, however, explained how keyless-entry systems installed at auto factories work and how they're becoming increasingly foolproof.
“For [General Motor Corp.'s] systems, for something like that to occur - at least for our recent vehicles - would be extremely rare,” said Tom Utter, lead keyless-entry-system engineer for the world's largest automaker.
In the mid-1990s, Mr. Utter and others said, keyless-entry signals combined fixed individual security codes with rolling codes that change with each use.
Rolling codes are encrypted so would-be thieves can't “grab” required codes with radio-frequency equipment.
Keyless-entry supplier TRW, Inc., has more than four billion possible individual codes it can use for DaimlerChrysler AG's Toledo-made 2002 Jeep Liberty and other vehicles. (Keyless entry is not offered on the Toledo-made Jeep Wrangler.)
Systems for many Jeep, Chrysler, and Dodge vehicles can be programmed so the keyless-entry fobs for one could open another, said Mike Marks, senior manager for the Liberty's interior electrical devices.
Keyless entries first are set up with a specific code for each automaker, allowing such programming to be possible while making it even more unlikely that a Ford's fob could open a Jeep instead of a Lincoln, said Casilda dede Benito, engineering director of TRW's automotive security systems.
Visteon has added other safety features to improve its keyless-entry systems, Mr. Gioia said. Recessed fob buttons help prevent accidental use, and the device is programmed so the driver door is opened on the fob's first push and the other doors on the second, he said.
The Dearborn, Mich., auto supplier is among companies looking into using biometrics, which use fingerprints or other physical characteristics as pass codes to open doors and start engines.
Germany's Siemens AG is supplying a keyless-entry system for some 2002 Cadillac models that requires only that the fob be within about three feet of the car to alert the system and, when the door is being opened, unlock the vehicle, said Brad Warner, a Siemens communications specialist.
“You don't have to push a button, you don't have to do anything,” he said.