The subscription-based OnStar monitoring and tracking system, best recognized for its ability to bail out motorists in traffic accidents via an automatic call to emergency agencies, is about to leave millions of customers out on their own. Operators will soon be signing off for some of OnStar’s longstanding customers because of a decision made by the Federal Communications Commission in 2002 that enables cell phone carriers to shut down their analog networks by February next year.

The decision will affect motorists with older cars that were designed to rely on those analog networks. What’s worst is that many parts of rural America are yet to have the digital networks installed. Some cars, especially post 2002 models can have their systems upgraded but others will become obsolete. Owners of GM cars will be the bulk of disadvantaged customers, but some Acura, Audi, Subaru and Volkswagen owners will also be affected.

The New York Times reports that major OnStar network Verizon Wireless has not commented about how it will dismantle its analog network, but experts agree that the most likely outcome will see the network shutdown in stages over the ensuing months. OnStar has created a Web site to alert customers to the coming changes.