[PDF] Pac Audio Accessories Installation Instructions - CARiD RP5-GM11 also provides data bus driven outputs such as retained accessory power (RAP), vehicle speed sensor (VSS), illumination, reverse trigger and parking brake. 1 radio select rotary switch on the side of the interface must be adjusted to the proper radio setting before plugging the PAC – Connecting cars and technology. Your total Life just got easier for aftermarket radio installers, and better for their customers. PAC now introduces RadioPRO Advanced. RadioPRO Advanced is the next generation of radio installation adapters. These new and improved aftermarket radio adapters are loaded with new features, so you can upgrade a vehicle’s radio without losing factory features.