The entry-model LCGM24 provides a warning chime retention with an onboard buzzer and 12v ACC output.
 
Retains all safety warning chimes
Provides 10 minute RAP output
Compatible with factory non-amplified audio systems and standard Bose audio systems
Provides 12v ACC output
 
It does not provide navigation outputs such as VSS, Reverse Output, or Parking Brake Outputs; please see the GM1A-R for a full-featured solution. Does not retain OnStar®. Please see OS-2X for an OnStar® solution.