Enrollment Surpasses 100,000 in First Month Following Announcement Oct 20, 2005 -- Detroit, Mich. - OnStar subscribers are responding enthusiastically to the opportunity to participate in the OnStar Vehicle Diagnostics program, another valued addition to OnStar's popular array of safety, security and peace of mind services. In the first month since OnStar launched the innovative, new, monthly e-mail vehicle diagnostic service, enrollment has surpassed 100,000 customers. "As we had expected, our subscribers have enthusiastically embraced OnStar Vehicle Diagnostics. Now, over 100,000 vehicles are sending their owners monthly e-mails to tell them how they are doing,'' said Chet Huber, OnStar president. "That's just part of what OnStar brings to GM's Total Value Promise, giving customers unique, important services and, in this case, at no additional price,'' he added. OnStar Vehicle Diagnostics automatically performs hundreds of diagnostic checks on four key GM vehicle operating systems - the engine/transmission, anti-lock brakes, airbag and OnStar. The vehicle is automatically programmed to send the results via e-mail to the owner each month. The unique e-mail report also provides maintenance reminders based on the vehicle's current odometer reading, remaining engine oil-life and other relevant vehicle ownership and OnStar subscription information. How OnStar's Vehicle Diagnostics Work About OnStar OnStar, a wholly owned subsidiary of General Motors, is the nation's leading provider of in-vehicle safety, security and communication services using wireless technology and the Global Positioning System (GPS) satellite network. OnStar is available on more than 50 GM models for 2005. By the end of 2007, OnStar will be a standard feature for GM's retail customers in the United States and Canada, covering all segments and prices except for some commercial vehicles. OnStar safety and security services include automatic notification of air bag deployment, stolen vehicle location assistance, emergency services, roadside assistance, remote door unlock, and GM Goodwrench remote vehicle diagnostics. OnStar Personal Calling allows drivers to make and receive hands-free, voice-activated calls from their vehicle. More information about OnStar can be found at www.onstar.com.