Serial Data Controlled Retained Accessory Power (RAP)
WARNING: This page is about a different car, the 2004 Pontiac Sunfire and 2004 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
Retained accessory power (RAP) is a vehicle power mode that permits the operation of the radio after the ignition switch is turned OFF. The radio will remain in operation until the drivers door is opened or until the RAP function timer reaches its shut-off limit.