ATLANTA — This month, phone carriers are starting a big switch -- phasing out 3G service to make more room for the faster 5G cell network. Consumer advocates said that change comes with a cost.

Channel 2 Action News investigative reporter Justin Gray learned important safety features on many cars will stop working in a matter of days if drivers don’t get critical updates. Some drivers will lose features permanently.

RELATED: See a list of impacted vehicles here

South Fulton resident Yvette Brace received a December letter from BMW explaining the automaker is discontinuing navigation and emergency features in her 2015 5 Series sedan this month for good.

“I received a notification through the mail that my car was going to be obsolete,” Brace told Gray. “Especially if you are driving with young children that safety feature is important, and it makes you feel safe driving in your car to know that button is there, and you can get help right away.”

Brace’s car is one of many makes and models where automakers are essentially walking away from critical safety and subscription features as wireless carries shut down 3G networks to make room for the 5G signal and bandwidth. It’s a move the wireless industry said has been public knowledge for at least five years.

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Some carmakers are offering to upgrade vehicles. Some models, like top tier 2018 to 2022 Hondas, need critical updates before 3G service sunsets this month. Others, including Hyundai, Lexus, Nissan, Toyota, and BMW, told drivers they will lose their connectivity in some models permanently.

“Automakers had plenty of notice this was coming,” said Channel 2 Consumer Advisor Clark Howard. Howard said he can’t believe automakers like BMW are telling customers their remote system won’t work and they won’t update them. “That is not the way a luxury brand should operate. It’s not the way they should treat their customers.”

Michael Brooks with the Center for Auto Safety said impacted drivers should be frustrated because features like SOS buttons and automatic crash detection are important. “I think it’s inevitable that it’s going to reduce the quality and efficiency of medical care that folks receive when they’re in crashes and there’s no one else around with them,” he said. “The big problem is the automakers and their people aren’t keeping up with the technology.”

Brooks and Brace said they fear drivers won’t realize they’re losing potentially lifesaving features until they need help and push that SOS button.

“I don’t think a lot of people are aware or even know that this is going to happen to them,” Brace said. “They just left us out in the cold.”

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