This Preliminary Information communication provides information to the technician about vehicles that the radio Radio/HVAC Display turns off and on at times, ABS, Service Traction System and Service StabiliTrak telltale lights come on, and or Service Steering Message displaying in the Driver Information Center and may experience heavier steering feel at low speed or static steering maneuvers. Technician may find Diagnostic Trouble Code C0800 set in the Electronic Brake Control Module. Technician will need to contact General Motors Technical Assistance Center for further assistance.