Officials Unlock Mystery of the Keyless Entry System Outages

It could've been the day any excitable person who considers The Matrix and Terminator films as practical survival guides dreads.

The day the machines take over the world.

That's what it might have felt like this week for some shoppers who parked near Kohl's at Brookside Marketplace and witnessed as their vehicles' keyless entry systems were mysteriously disabled, only to suddenly work again once the auto was moved away from the area.

But Tinley Park officials and technicians brought in by Kohl's were able to discover and repair the problem caused by malfunctioning sensors in the store's automatic door and security systems, said Pat Carr, the village's Emergency Management Agency director.

No, it wasn't a technological revolt bent on world domination, but it was enough to frustrate and alarm some drivers at Brookside Marketplace on Sunday and Monday, as Sun-Times Media first reported. The village fielded calls from about 20 to 30 people who experienced trouble with their entry systems, Carr said, adding that Kohl's handled most of the reports of car problems.

A store manager would not comment on the problem and directed all questions to Kohl's corporate headquarters in Wisconsin. A Kohl's spokeswoman had not responded to emailed questions at the time of this report.

Earlier in the week, theories about the cause of the disruption ranged from power lines, NASA satellites and interference from a pirate radio station's radio waves, according to the Sun-Times Media report.

But Patch spoke with Carr on Thursday, and he helped pull back the curtain on the strange outages.

The Real Cause? A Case of Crossed Signals

Far from a common occurrence, incidents of car remote entry systems suddenly not working have been cropping up across the country, Carr said. So the individuals investigating this case turned to those, looking for clues and similarities, he added. That's how the problem with the store sensors and the car systems was uncovered.

Here's how it breaks down, according to Carr:

• Stores like Kohl's have automatic door and security systems that have sensors that are used to pick up signals from things such as the radio-frequency identification (RFID) tags on merchandise.
• These systems operate on a similar frequency as the keyless entry systems in automobiles. (The frequency is an industry standard, assigned by the Federal Communications Commission, Carr said.)
• The store sensors can malfunction in such a way that they cross signals with a car's remote entry system.

"If [the sensors are] out of adjustment and something fails on them, the frequency automatically goes out," Carr said. "The frequency starts transmitting and starts interfering with the keyless entry system."

Depending on the locations of the frequency receivers and transmitters, the affected area could be anywhere from 75 to 300 feet, Carr added.

Once this was determined to be the cause, technicians brought in by Kohl's were able to repair the problem areas Monday, Carr said. A Kohl's manager Thursday would not confirm if the trouble had been eliminated. Carr said the village only received one call about a keyless entry not working once the fixes were made.

Other businesses in the shopping center also were appraised of the sensor issue, so they could make sure their systems were working properly, Carr added.

Why Was This a Village Issue?

Although this all happened on private property, village officials were brought in because of safety concerns, Carr said. Not only did the entry system outages have the potential to leave people stranded in the parking lot, they also could have been the sign of criminal activity. Thieves have been known to use devices that disrupt security sensors, and the village wanted to rule out that possibility, Carr said.

"We don't think it's any type of criminal element. … We checked police records and had no calls for burglaries or thefts," he said. "No suspicious people were seen in the parking lot. Based on what we found, … [the sensor malfunction] is the most logical explanation.

"We live in a tech world with all these different frequencies, from WiFi to cell phones. ... There's a lot of potential frequency interference out there."

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