PAC OS-1 Factory Integration Adapter

Connect a new car stereo and retain OnStar® and the Bose® audio system for select GM vehicles

  • PAC OS-1 Factory Integration Adapter



Our take on the PAC OS-1 Factory Integration Adapter

by Charlie Pastorfield

PAC's OS-1 factory integration adapter lets you replace a General Motors radio (without RDS) with an aftermarket receiver while maintaining operation of the OnStar® system and the GM Bose® amplifier and speakers. The kit includes:

  • the OEM-1 premium sound system interface, which allows quick connection of an aftermarket receiver (or an additional amplifier) to the GM Bose system, without the need to cut wiring;
  • the OS-1 adapter, which allows the use of the OnStar system with an aftermarket receiver. The OS-1 has on-board switching and built-in amplification that allows audio from the OnStar system to play through the two front speakers (factory or replacement) when OnStar is active, while muting the replacement radio.

The OS-1 can also send OnStar audio to an external set of speakers if desired. There are separate right and left gain controls for OnStar audio, and an LED indicator that turns on when the OS-1 receives an "On" command from the OnStar® system. Dimensions: 4-13/16"W x 1-1/16"H x 2"D (OS-1 adapter). Please enter your vehicle information or call an Advisor at 1-888-955-6000 to find out if this model is compatible with your vehicle.

Important Note: The OS-1 kit will interface with GM Delco/Bose radios that do NOT have the "RDS" option. If there is an "RDS" logo on the radio face, the OS-1 kit will not work. Warranty: 1 year.

Note: Most vehicles will require additional installation parts — please identify your vehicle if you haven’t done so, then check here for a list of parts. You can also call an Advisor for more information.


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What's in the box?

Download owner's manual

  • OS-1 GM OnStar Interface adapter with attached 7" wire harness (6-pin Molex plug on end)
  • OEM-1 Factory Sound System Interface
  • 12" OS-1618 harness
  • One 8" OS-RAD harness with attached Emitter
  • One 7" AMP-GM21A harness
  • Installation Instructions

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Applications: The OS-1 BOSE is an interface that allows for the replacement of a GM factory radio, that doesn't have RDS, and maintain the operation of the OnStar navigational system and the factory GM Bose sound system. The OS-1 BOSE has on board switching and amplification that allows the audio from the OnStar system to play through the front speakers when OnStar is active, and mutes the replacement radio.

Compatibility: The OS-1 BOSE is compatible with the following select 2002 and older General Motors vehicles: Chevy Avalanche, Cadillac Escalade, Chevry Silverado, GMC Sierra, Chevy Surburban, Chevy Tahoe, and GMC Yukon, plus 2000 and older Chevy Blazer, GMC Jimmy and Chevy Lumina. It will also work in some 1999-2003 Pontiac Grand Prix and 98-99 Bonneville. The OS-1 BOSE will interface with all GM radios that use 21-pin/9-pin connectors and have Bose amplifier/speakers. If there is an "RDS" logo on the face of the radio, this interface will not work. Please check the Crutchfield Vehicle Selector for compatibility with your vehicle.

Contents: The OS-1 BOSE interface consists of the OS-1 On-Star interface and the OEM-1 Premium Sound Interface, plus the wire harnesses that plug between the two interfaces and the factory sound system and On-Star system.

Left and Right Gain Controls: The OS-1 adapter has independent left and right controls that adjust the level of audio coming from the OnStar system.

LED Indicator: This is an indicator on the OS-1 that lights up when OnStar is active.

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PAC OS-1 Factory Integration Adapter Reviews

Average Customer Review:

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5 out of 5

PAC OS-1 Factory Integration Adapter

Written By josh f, Eau Claire, WI on Tuesday, May 07, 2013
Crutchfield Customer Review (What's this?)
Works great and the clutchfield support was dead on! I would recommend buying through them. Thanks clutchfield for making my install a breeze!
Works great
Was this review helpful?    Yes | No
5 out of 5

Perfect Integration

Written By MattyP, Wichita, KS on Wednesday, December 26, 2012
Crutchfield Customer Review (What's this?)
Needed this adapter to hook up a JVC head unit to my Bose-equipped 2001 Suburban. The install went smooth as anything, the instructions are fairly clear but of course Crutchfield's tech guys are the best in the business to help so don't even sweat it. Since you will be connecting loose-end wires together to your head unit wiring harness, you'll need to purchase some wiring connections. I recommend the telephone-wire type connectors that you can get at the home improvement store (you put both wires into a little fastener and clamp down with pliers and boom...done). Everything hides behind the head unit somewhere in your dash and away you go. Easy breezy.
Seemless and easy
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4 out of 5

PAC OS-1 Factory Integration Adapter

Written By Derek, OKC, OK on Sunday, May 24, 2009
Crutchfield Customer Review (What's this?)
Good product, does what is advertised. The only downside is the relay in the harness. Mine failed within a couple of hours of operation and ended up removing it all together. Once the relay was removed everything went back to working perfectly.

2 out of 3 people found this helpful
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4 out of 5

Bose system adapter

Written By BK's account, Montgomery, AL on Friday, February 08, 2008
Crutchfield Customer Review (What's this?)
This adapter was used to integrate a Kenwood DVD into a 2001 Yukon Denali. Supports the On-Star and seamlessly installs to use the stock bose amps and speakers. One note, the steering wheel remote functions will not work. You'll need a separate RF remote adapater for that.
Also found the the OEM-1 component is not required, in fact the system works better without it (less road noise).

With this adapter, it was easy to install an aftermarket stereo.

Recommend the Crutchfield website provide more detailed installation instructions.
18 out of 18 people found this helpful
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2 questions already asked

I am wondering if I need to purchase this product because I am not using the on star and do not plan on using it. I am keeping all of my factory Bose speakers, as well as adding a sub to the trunk space. Will the new head unit, stock speakers and subwoofer still fiction correctly without this product? [ Sean  Mar 17, 2014 ]
1 answer
  • You will want to contact an Advisor by phone (1-800-324-9695) or online chat to discuss compatibility with your factory system. They will be able to pull up your vehicle and see if this is needed. [ Jeff Staff  Mar 18, 2014 ]
looking to buy single din pioneer stereo to replace oem bose head unit want to keep stock Bose speakers and oem amp I also want to add a separate amp for my subs in trunk Is this Adapter what I need? thanks [ phil  Mar 13, 2014 ]
1 answer
  • You will want to contact an Advisor by phone (1-800-324-9695) or online chat to discuss compatibility with your factory system. They will be able to pull up your vehicle and see if this will integrate. If it does not, then they will also be able to discuss other options with you. [ Jeff Staff  Mar 13, 2014 ]

For a more in-depth review and enhanced detailed information on the PAC OS-1 Factory Integration Adapter, please visit the Crutchfield website product page (/ISEO-rccbcspd/p_127OS1BOSE/PAC-OS-1-Factory-Integration-Adapter.html ).

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