GM Service Manual Online
For 1990-2009 cars only

The vehicle can be programmed to sound the horn three times and unlock the driver's door when all doors are closed and there is a keyless access transmitter inside the interior of the vehicle. When the driver's door is reopened, the key in reminder chime will sound continuously. The vehicle will remain locked only when at least one transmitter has been removed from the vehicle and both doors are closed. See Vehicle Personalization .