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Metra GMOS-04 Wiring Interface

Connect a new car stereo and retain OnStar®, the audible safety warnings and chimes, and the Bose® audio system in select GM vehicles

Item # 120GMOS04

Metra's GMOS-04 GM radio replacement interface lets you replace the factory radio in select OnStar-equipped 2000-up...

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Metra's GMOS-04 GM radio replacement interface lets you replace the factory radio in select OnStar-equipped 2000-up...

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Item # 120GMOS04

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$84.99

About the Metra GMOS-04 Wiring Interface

Metra's GMOS-04 GM radio replacement interface lets you replace the factory radio in select OnStar-equipped 2000-up GM vehicles using the existing wiring and connectors. Even if you don't subscribe to OnStar, you'll need this adapter to connect an aftermarket stereo.

Metra's GMOS-04 GM radio replacement interface lets you replace the factory radio in select OnStar-equipped 2000-up GM vehicles using the existing wiring and connectors. Even if you don't subscribe to OnStar, you'll need this adapter to connect an aftermarket stereo.

Once you connect your in-dash receiver to the interface, you'll get the great sound you want, and keep these important features intact. The Bose amplified speakers and the OnStar system will operate with your new radio, as well as the door chime and audible safety warnings. This interface gives you convenient plug-in connections for the Axxess steering wheel control adapter (not included) that works with most aftermarket stereos – that means less wiring work for you.

Also, once you turn off the ignition in these GM vehicles, the factory radio continues to play until you open the door. This interface maintains that function with your new aftermarket radio. This interface is compatible with select 2000-and up GMC, Chevrolet, Oldsmobile, Cadillac, Pontiac, Isuzu, and Hummer vehicles. Warranty: 1 year.

Important Note: If you haven't done so already, please enter your vehicle information or call an Advisor at 1-888-955-6000 to find out if your GM vehicle's warning chimes are integrated with the factory radio. If so, certain warning chimes in your vehicle may be disabled by installation of an aftermarket receiver. You must use the recommended Crutchfield interface to retain the warning chimes. Failure to do so may result in serious injury or death.

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What's in the box:

  • GMOS-04 interface module
  • 16-pin harness with stripped leads
  • 18-pin harness to 12-/24-pin GM harness with stripped leads
  • Installation Instructions
MFR #GMOS-04

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Metra GMOS-04 Wiring Interface reviews

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More details on the Metra GMOS-04 Wiring Interface

Stacey B.

Product Research

Features

Overview: The GMOS-04 interface is designed to let you replace the OEM radio with an aftermarket unit in amplified GM vehicles and retain full functionality of the OnStar system as well as all safety and warning chimes. The GMOS-04 will also retain the retained accessory power convenience features. This interface has the capability of adjusting chime and OnStar volumes as well. In addition to these features, the GMOS-04 has the required outputs for the installation of a navigation radio (including VSS, parking brake, and reverse outputs).

Vehicle Compatibility Chart: The GMOS-04 works in the following 2000-up GM vehicles.

Make Model Year
Buick Allure 2005-2009
Century 2004-2005
Lacrosse 2005-2009
Rainier 2004-2007
Rendezvous 2002-2007
Terraza 2005-2008
Cadillac Escalade 2003-2006
Chevrolet Avalanche 2003-2006
Cavalier 2000-2005
Corvette 2005-2010
Express 2003-2007
Impala 2000-2005
Malibu 2001-2004
Monte Carlo 2000-2005
Silverado 2003-2007
SSR 2003-2006
Suburban 2003-2006
Tahoe 2003-2006
Trailblazer 2002-2009
Uplander 2005-2008
Venture 2000-2005
GMC Envoy 2002-2009
Savanna 2003-2007
Sierra (Classic) 2003-2007
Yukon/Denali 2003-2006
Hummer H2 2003-2007
H3 2006-2009
Isuzu Ascender 2003-2008
I-Series Pickups 2006-2008
Oldsmobile Alero 2001-2004
Bravada 2002-2004
Intrigue 2002
Silhouette 2000-2004
Pontiac Aztec 2001-2005
Grand Am 2001-2005
Grand Prix 2004-2008
Montana 2000-2005
Sunfire 2000-2005
SAAB 9-7x 2005-2009
Saturn Relay 2005-2007
Note: Please consult Crutchfield's Outfit My Car for your specific vehicle and application.

OEM Steering Wheel Control Compatible (optional): The GMOS-04 features a right-angle 3.5mm connector that lets you keep your GM vehicle's OEM steering wheel controls via the optional Axxess Steering Wheel Control Interface (120ASWC1, sold separately).

Note: The GM vehicle must have factory steering wheel controls to retain access to the factory customization menu, once the factory radio is replaced with an aftermarket head unit.

OnStar and Chime Volume Adjustment: The volume is adjustable for both the OnStar output and the warning chime.

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Customer Q&A

Q
Crutchfield asked: Why did you buy this?
A
I tried the Crux interface and it didn't work so I opted for this more pricy option. [ Glen  Mar 20, 2019 ]
A
Fits my application for what I need [ Kwamane  Feb 28, 2019 ]
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to install a reciever [ Omar  Dec 19, 2018 ]
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That was need [ Jay  Nov 15, 2018 ]
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came with [ Joseph  Sep 26, 2018 ]
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Required for installation. [ Dexter  Sep 19, 2018 ]
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Needed to make a an easier connection. [ GEORGE HALL  Sep 02, 2018 ]
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Package [ Greg  Aug 26, 2018 ]
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Required accessory automatically recommended by Crutchfield when I purchased a Pioneer MVH-S600BS head unit for my 2004 Pontiac Grand Am. [ Bruce  Aug 11, 2018 ]
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Crutchfield recommended it to complete my installation correctly. [ Kevin  Aug 06, 2018 ]
A
The price was the best when compared to local shop prices! Thanks Crutchfield! [ Kevin C.  Jul 18, 2018 ]
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Because Hummers are kind of a pain. [ WILLIAM  Jun 07, 2018 ]
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To keep the existing features of my Onstar and Safety warnings and make the installation easier [ Chester  May 04, 2018 ]
A
I wanted to retain the safety devices, and amp connections for my Hummer H3 Alpha, but I don't have steering wheel controls so I didn't need the more expensive one. So this worked out. And also it'll be here by the weekend, and the store in town was twice the price! [ Patick Casey  Apr 24, 2018 ]
A
To go in my 2006 Pontiac Prix gt [ Quenell  Apr 03, 2018 ]
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I'm an electrician by trade, I can cut, splice, tape,with the best of them... but you can't beat a plug and play installation... you just can't [ John  Mar 30, 2018 ]
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advisor [ Tony  Mar 08, 2018 ]
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I chose this because this car is high end and stores do not stock the proper parts! [ Dawn  Dec 17, 2017 ]
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fair priced [ Kenya  Oct 22, 2017 ]
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Because you said I needed it [ Mark  Oct 05, 2017 ]
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to make it work [ JEFFREY  Sep 23, 2017 ]
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A necessary item to get the job done easier. [ DOUG  Sep 20, 2017 ]
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Easier hookup [ Charlie   Aug 25, 2017 ]
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Required for the installation of my aftermarket radio. [ Christopher  Aug 24, 2017 ]
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It was recommended for use with my 2007 Trailblazer SS with bose system w/o navi. [ Jon  Jul 23, 2017 ]
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to retain factory chimes and alerts and hopefully connect to stock bose amp and speakers, we will see, recommended install kit [ Anthony  Jun 22, 2017 ]
A
I was referred to this product for my Pontiac. I installed an aftermarket radio, and my dash stops working and lights flash from traction control and other errors. Hoping this will help fix the problem. [ Jody  Jun 18, 2017 ]
A
the reviews looked and and im hoping its better than the pac. i received two pacs and there crap [ Thomas  Jun 04, 2017 ]
A
needed for the install on stereo [ brandy  Mar 20, 2017 ]
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Better reviews [ Robert  Mar 11, 2017 ]
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hope it will work [ William  Feb 27, 2017 ]
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hey it beats cutting up the factory wiring harness for the head unit [ Ryan  Feb 16, 2017 ]
A
Crutchfield is a company that has been around for years i trust in their prouducts and in the crutchfield name. [ Michael  Feb 10, 2017 ]
A
Great price! And had a lot of good reviews! [ Dakota  Jan 25, 2017 ]
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the one in truck shorted out after low voltage and tried to remote start [ scott  Jan 13, 2017 ]
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To connect my My aftermarket pioneer head unit to my bose system [ Benjamin  Oct 26, 2016 ]
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Required [ Robert  Oct 24, 2016 ]
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Needed it to for my stereo :-) [ patricia  Sep 14, 2016 ]
A
It's the he only kit try that retains my xm tuner in my Silverado. [ HENRY  Aug 03, 2016 ]
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Needed for my 03 suburban bose system. [ Lucas  Jun 11, 2016 ]
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For my 2008 Buick LaCrosse aftermarket stereo install [ Matthew  Jun 05, 2016 ]
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Recommended and required. [ Christopher M.  Apr 23, 2016 ]
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it was required for installation for my vehicle. My vehicle came with a factory bose amp [ ANDREW  Apr 03, 2016 ]
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Recommend with stereo [ jeff  Mar 18, 2016 ]
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For the Bose and On star compatability. [ Orlando  Mar 16, 2016 ]
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You need it! [ CASEY  Feb 28, 2016 ]
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recommended by Crutchfield [ Jeff  Feb 25, 2016 ]
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I choose this product because it would allow me to retain my factory amp [ gomezj22  Feb 22, 2016 ]
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ability to integrate with the factory Bose system [ Joseph  Jan 12, 2016 ]
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needed to install radio [ Mac  Dec 14, 2015 ]
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Called Crutchfield and Advisor looked it up and told me this is the wiring harness I need for my truck [ Nathan  Dec 05, 2015 ]
A
Support Rep parker recommended it for my installation. [ sidekixx1  Dec 05, 2015 ]
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16 questions already asked

Q
What do you do if your aftermarket radio doesnâ??t receive power I have a 2002 Pontiac grand am and I have it all wired up exactly how it goes but doesn't want to power it?
[ Travis  Sep 25, 2019 ]
1 answer
A
Hi Travis, sorry to hear you're having trouble with your stereo. It will be hard to even give a good guess on what could be going on with that stereo. Did you purchase your gear from us here at Crutchfield? If you did make your purchase from us, our tech support team will be more than happy to go over everything with you, perform troubleshooting, and find the solution that will get your stereo up and running. You will find their number listed online when you log into your account, or it can also be found with the invoice/shipping confirmation email we would have sent you. If you did not purchase your gear from us, I suggest contacting technical support of the company you worked with, or the manufacturer of your stereo. If nothing can be found through those channels, you may need to speak with a local stereo installer, or mechanic in your area.
[ Jess  Oct 09, 2019 ]  Staff
Q
Will this allow me to hook aftermarket radio and subwoofer in a 2002 gmc envoy with bose sound system?
[ Jacob  Jul 18, 2019 ]
2 answers
A
It should I it worked perfect in my 02 trailblazer
[ Frankie  Jul 19, 2019 ]
A
Yes I used it in my 07 Trailblazer ss with bose
[ Chris  Jul 18, 2019 ]
Q
i have a 2004 gmc envoy xuv with bose system with amp and onstar i got 2 different wiring harnesses connected everything and the radio has power but there is no sound from the speakers at all would this harness work?
[ ricky  May 04, 2019 ]
1 answer
A
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer.
[ Krissy  May 14, 2019 ]  Staff
Q
Will this work on a 2004 Sierra Denali with luxury Bose amplified sound system?
[ l  Feb 06, 2019 ]
2 answers
A
Yes it should it worked on my Silverado with the Bose amp abs speakers
[ SCOTT  Feb 08, 2019 ]
A
Your product adviser can answer this question, but I myself, will say yes. I have a 2009 HUMMER H3 Luxury Bose amplified system in it and also the OnStar system, although I don't use the OnStar. Very easy to install, but be sure to read the settings instructions as they have two different ways to set the sound of the door/warning chimes and a different way to set the volume for the stereo audio.
[ Darren  Feb 06, 2019 ]
Q
will this work on a 2008 gmc envoy with bose?
[ Frank  Dec 11, 2018 ]
3 answers
A
I don't know about a 2008 Envoy. It worked on a 2006 Silverado.
[ Britt  Dec 12, 2018 ]
A
Yes is a must
[ Angel A.  Dec 12, 2018 ]
A
yes this should work on your 2008 bose system
[ MAUREEN  Dec 11, 2018 ]
Q
Can this kit be used to add aux 3.5 jack to an Envoy factory radio?
[ Ty  Dec 05, 2018 ]
1 answer
A
This harness is used to install a new radio into a compatible vehicle. The 3.5mm plug is meant to work with the ASWC-1 steering wheel radio control interface. However, we might have an adapter to give your vehicle an aux audio input. I recommend contacting an advisor on 1-800-324-9695 to check for an aux input adapter My Bio: https://www.crutchfield.com/bio/Paul
[ Paul  Dec 12, 2018 ]  Staff
Q
Will this retain my monsoon amp on my 2002 Pontiac grand am?
[ Carlos  Feb 20, 2018 ]
1 answer
A
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.
[ Krissy  Mar 01, 2018 ]  Staff
Q
Will this fit a 2004 Grand Prix GT2 with the monsoon sound system and steering wheel controls? I am trying to install a Pioneer AVH-290BT double din radio. Thanks
[ Kyle  Jul 02, 2017 ]
1 answer
A
You can check to see if this will fit your vehicle by using our Outfit My Car tool: http://www.crutchfield.com/car/carselector.aspx For additional details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle.
[ Krissy  Jul 03, 2017 ]  Staff
Q
Will this also maintain functionality of rear dvd entertainment system?
[ Scott  Jun 11, 2017 ]
1 answer
A
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.
[ Krissy  Jun 11, 2017 ]  Staff
Q
Will my new radio still get power without the harness?
[ Biggie  May 02, 2017 ]
2 answers
A
Your radio can get power without the harness, but the harness makes the installation so much easier.
[ D  May 02, 2017 ]
A
No. Not unless you cut and splice your factory harness which I would not recommend at all.
[ PATRICK  May 02, 2017 ]
Q
Will it work on a 06 monte carlo ?
[ Mikey  Mar 04, 2017 ]
1 answer
A
For additional details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle.
[ Kenny  Mar 04, 2017 ]  Staff
Q
I have the GMOS-04 connected today and all is well. I want to bypass the BOSE amp, install new amps and speakers, but maintain the chimes. If my head unit has the RCA's for the new amps (bypassing the BOSE), how can I wire this so the chimes still work, but don't get amp'd to some huge level like my speakers? Thanks, Jim A
[ Jim  Jun 30, 2015 ]
2 answers
A
On the wiring harness is a level adjustment leave your door open and adjust it with door open it only Adjust the chime level with the door open close for to adjust music level
[ TIM  Jul 03, 2015 ]
A
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: http://community.crutchfield.com. Or try our online support center: http://crutchfield.custhelp.com/app/answers/list/kw/.
[ Jeff  Jul 01, 2015 ]  Staff
Q
I have a 2006 Corvette coupe with Bose (but no Onstar) and am wondering if this product will maintain the current Sirius/XM receiver or if I have to buy a new Sirius/XM receiver?
[ Netcruizer99  Mar 15, 2015 ]
2 answers
A
Thank you!
[ Netcruizer99  Mar 16, 2015 ]
A
For details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle.
[ Krissy  Mar 16, 2015 ]  Staff
Q
Will this harness connect the OnStar mic to the new head unit, or do I need to install the 2nd mic that came with the unit?
[ Dennis  Feb 26, 2015 ]
1 answer
A
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.
[ Krissy  Feb 27, 2015 ]  Staff
Q
Will this work on my vehicle, 2003 Chevy Tahoe with Bose system? I do not have OnStar or steering wheel controls.
[ Jeremy  Apr 16, 2014 ]
1 answer
A
For details on installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle.
[ Krissy  Apr 16, 2014 ]  Staff
Q
do I need another adapter to keep the steering wheel control on my 2004 Pontiac Grand AM with monsoon amp?
[ John C  Jan 05, 2014 ]
1 answer
A
The ability to retain steering wheel controls with aftermarket receivers will be determined by the receiver you are using and the vehicle you have. For full information on this type of integration (including the parts you will need) please contact an Advisor by phone or online chat.
[ Jeff  Jan 06, 2014 ]  Staff
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