Check the listing for details. Radio Replacement Interface Harness w/ OnStar Retention for Select GM Vehicles. Condition: New. Listed at 119.99 USD. Radio Replacement Interface Harness w/ OnStar Retention for Select GM Vehicles Upgrade your GM vehicle's audio system while retaining the functionality of OnStar on Select GM Class II Vehicles with or without the BOSE Sound System. This wiring harness interface ensures a seamless installation when replacing the factory radio. It allows you to retain the functionality of OnStar, ensuring you can still utilize its features and services. Additionally, the wiring harness interface generates all safety warning chimes, maintaining the necessary audible alerts for a safe driving experience. Upgrade your GM car stereo system while preserving important features with this convenient and reliable wiring harness interface. Rear Seat Entertainment activation Plug-in-connection for steering wheel control module (SWI-CP2 or SWI-RC) In-field updateable firmware via USB Chime Module Included, with 4 level adjustability Retains OnStar® when the factory radio is replaced Retains Bose amplified audio system (if equipped) Provides 10 Amp 12-volt accessory output Retains all safety warning chimes Navigation radio ready Maintains a “healthy” status on the Class II data bus Retains Rear Seat Radio Controls Retains Rear Seat Audio (connects to aftermarket radio AUX input) Plug-in installation for vehicles with 24-pin harness