Radio Replacement Interface for Select GM Vehicles with OnStar, GM-LAN Data-Bus, and With/Without Bose

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The PAC-OS4 is a plug and play interface that all for the replacement of a GM GMLAN Factory radio. It maintains the operation of OnStar in vehicles with Bose sound systems, amplified audio systems, and also audio systems without an external amplifier. The OS-4 has on-board switching that allows audio from the OnStar system to play through the two front factory speakers. This interface retains all factory warning chimes, audible turn signal indicators, factory XM Radio, and rear parking assist system. This is an all-in-one interface that eliminates the needed for multiple harnesses in specific GM LAN Vehicles.

General Features:

  • Replacement interface for select GM Vehicles with OnStar, Bose, and GM LAN Data Bus
  • Compatible with or without factory amplified audio system
  • Can be used if the vehicle does not have OnStar
  • Compatible with or without Bose systems
  • Provides 12 Volt RAP Output wire
  • Retains the 5.1 Digital audio system in select GM Vehicles
  • Adjustable OnStar volume using the factory steering wheel controls
  • Factory XM Retention (vehicles with rear seat controls)
  • Retains factory rear park assist sensor system
  • Provides a direct plug and play in to any PAC SWI Interface
  • Retains factory Bluetooth (features and functions)
  • Latest version installed
  • 1-year Manufacturer's warranty
  • Check the General Installation Manual to see basic instructions for the PAC OS-4

Compatibility List:

  • Chevrolet:
    • 2007 - 2009 Tahoe
    • 2007 - 2009 Suburban
    • 2007 - 2009 Avalanche
    • 2007 - 2009 Silverado (Non-Classic)
    • 2006 - 2009 Impala
    • 2006 - 2007 Monte Carlo
    • 2007 - 2008 Express
    • 2007 - 2008 Equinox
  • GMC:
    • 2007 - 2009 Yukon Denali
    • 2007 - 2009 Sierra (Non-Classic)
    • 2007 - 2009 Acadia
  • Cadillac:
    • 2007 - 2009 Escalade / ESV / EXT
    • 2007 - 2009 SRX
    • 2007 - 2009 DTS

Harness Features

Vehicle Sound System
This refers to what kind of sound system the vehicle has. Premium audio systems are generally name brand systems (such as JBL, Bose, Rockford Fosgate, etc) that have been installed inside a vehicle when it leaves the factory. Often they more advanced systems, complex wiring, factory amplifiers, and other features that can make installing aftermarket component difficult.
Premium Sound
Main Harness Function
Different installations on different vehicles require different harnesses. This type is what the harness is considered. Each wiring harness we sell serves a purpose such as installing an aftermarket car stereo, integrating an aftermarket amplifier with your factory car stereo, connecting Bluetooth to your factory car stereo, and more.
Connect/Install an Aftermarket Car Stereo
Additional Harness Features
The various features that the wiring harness provides to your car stereo and/or audio system.
OnStar Retention
Retains Factory Bluetooth
Compatible Vehicle Make
Allows you to view only items that are compatible with your vehicle's make. Does not guarantee that it will work with your vehicle year or model.
Compatible Vehicle Make and Model
The model of vehicle that this vehicle specific product is designed for. Please keep in mind that engine variations can affect the compatibility of the products.
Cadillac Escalade
Cadillac SRX
Chevy Avalanche
Chevy Express Van
Chevy Impala
Chevy Monte Carlo
Chevy Silverado
Chevy Suburban
Chevy Tahoe
GMC Acadia
GMC Sierra
GMC Yukon

Premium Harness Features

Factory System Amplification
This refers to the factory sound system and whether the item is compatible with amplified or non-amplified systems.
Compatible Premium Audio Systems
Some vehicles have higher end audio systems installed in them by the manufacturer. This specifies which premium audio systems this item is compatible with.
Standard Bose
On-Star Compatible
This means that the harness is compatible with vehicles that have On-Star built-in.
GM-LAN Compatible
This means that the item is compatible with GM-LAN systems.

Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider

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Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: PAC OS-4-OPEN BOX