The PAC RP4-GM32 is an all-in-one radio replacement and steering wheel control (SWC) interface designed for select General Motors vehicles equipped with 29-bit LAN radios and factory navigation. This innovative RadioPRO4 interface allows for the seamless installation of an aftermarket car stereo while ensuring the retention of crucial factory features, saving both time and money during installation.

This interface comes pre-loaded with amplifier retention and SWC software, along with navigation-based output signals. It retains factory features such as steering wheel controls, allowing for dual command functionality with short press and long press options. It also preserves the factory amplifier (including Bose audio systems), safety warning chimes, rear seat controls (RSC), and retained accessory power (RAP). Additionally, the RP4-GM32 maintains back-up sensors and park assist functionality, and provides activation for factory rear seat entertainment (RSE).

For aftermarket navigation receivers, the RP4-GM32 provides essential data bus driven outputs including vehicle speed sensor (VSS), parking brake, reverse trigger, and illumination. The interface is in-package updatable using the PAC-UP interface updater (sold separately), ensuring compatibility with future firmware updates. Please note that this interface does not retain OnStar functionality; the RP5-GM32 is required for OnStar retention. Also, premium factory amplified systems will not retain fade control, as neither the aftermarket radio nor the RP interface can control the amplifier's fader.