General Motors Corp.'s OnStar telematics service says up to 500,000 customers will lose service in 2008 due to a major infrastructure switch from analog to digital networks.

But Troy Clarke, president-GM North America, says the auto maker won't leave customers in the lurch. Clarke says he expects an announcement from OnStar management soon.

OnStar anticipates 12.5% of its 4 million subscribers will be dropped in February 2008.

The expected outage follows a 2002 rule by the Federal Communications Commission that allows cell-phone service providers to switch off their analog networks beginning in February 2008. OnStar partners, such as Verizon Wireless, are expected to do just that.

OnStar relies on both digital and analog networks to connect with its subscribers. Once the analog network is shut down, car buyers who purchased an OnStar-equipped vehicle before 2002, as well as owners of some '02-'04 models, will find their OnStar links severed.

OnStar says it is coordinating with dealerships to install the necessary hardware and will be contacting customers. OnStar will update their system for a $15 fee.