Axxess GMOS-044 Wiring Interface

Connect a new car stereo and retain OnStar® and safety warning chimes in select 2011-up GM vehicles

Save with a compatible car stereo with a compatible car stereo
  • Axxess GMOS-044 Wiring Interface


  • Axxess GMOS-044 Wiring Interface


Our take on the Axxess GMOS-044 Wiring Interface

by Zak Billmeier

The Axxess GMOS-044 GM interface lets you replace the factory radio in select OnStar-equipped 2011-up GM vehicles using the existing wiring and connectors. Even if you don't subscribe to OnStar, you'll need this interface to connect an aftermarket stereo.

Connect the GMOS-044 to your aftermarket radio, mount the module, and plug it into the existing factory plug. Get the great sound you want, and keep all of the important safety features intact. You can adjust volume settings for OnStar as well as the safety chimes. 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.

Read more

This interface is compatible with select 2011-and up General Motors vehicles. 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 this item is compatible with your vehicle. 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.

Hands-on research from the Crutchfield Labs (what are the Labs?)

Product Research
What's in the box?

Download owner's manual

  • GM OnStar/chime retention interface module
  • Connecting harness with multiple connectors: 22-pin / 16-pin / 12-pin / 30-pin / 2 RCAs / Minijack / Relay
  • Installation Instructions

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team — they open the box, verify contents, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.


Overview: The GMOS-044 lets you replace the factory radio in select GM vehicles with an aftermarket head unit. It works in both amplified and non-amplified factory audio systems and is designed to retain OnStar and the warning chimes that are normally lost when the OEM radio is removed. It also provides a 12-volt accessory output for aftermarket radio operation. Additionally, the GMOS-044 provides a Mute, Parking Brake, VSS (speed sense), and Reverse outputs to make installing an aftermarket navigation unit less time consuming.

Vehicle Compatibility: The GMOS-044 works in select GM vehicles. Please consult the Crutchfield Car Selector to confirm compatibility with your specific vehicle.

OEM Steering Wheel Control Compatible (optional): The GMOS-044 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 & Chime Volume Adjustment: The volume is adjustable for both the OnStar output and the warning chime.

Review this product
Great Gear Giveaway rewards card

Submit a review and then enter to win a $500 rewards card

Axxess GMOS-044 Wiring Interface Reviews

Average Customer Review:

1 people say:

Review this product:

Thanks for taking the time to share your experiences about this product. Please be sure to focus your comments on the product itself. Read our Review Guidelines for more information.

Your email won't be visible. Please use the email address that is associated with your order.
(e.g., JohnD) Your review will be signed using the display name and location
(e.g., Charlottesville, VA)

Click on a star to rate the overall product on a scale of 1-5
1500 characters left
Attach a YouTube Review
Crutchfield Video Review Guidelines
  • Only submit videos that you made or are authorized to use.
  • Do not submit videos that contain music, video or visuals that are copyrighted and belong to someone else.
  • Please see our Review Guidelines for more information.
500 characters left
500 characters left
Filter by rating:
3 out of 5

it adapts

Written By Bill H, Lexington, KY on Tuesday, March 04, 2014
Crutchfield Customer Review (What's this?)
i still have the main display in my chevy cruze hooked up. it is annoying because i cant change the date or time or anything.
it kept the door chimes and turn signal clicker sound.
can't adjust any settings.
Was this review helpful?    Yes | No

1 question already asked

Does it support rear parking assist sensor warning sounds? [ Darrell  Mar 30, 2014 ]
1 answer
  • Good question! However I am not sure if it retains the reverse warning chime. My car doesnt have that feature. I would suggest you give a call into axxess support before you buy. Their number can be found on axxessinterfaces dot com. they have much more know how on these gmos harnesses than Crutchfield support does. They can be tricky. I tried doing it myself once and it didn't work out well. Crutchfield sent me a replacement and I just broke down and had the local big box store put it in for 95 bucks. Works flawlessly now. Don't know if it was me or the first unit I had. Oh well. Good luck! [ Michael   Mar 31, 2014 ]

For a more in-depth review and enhanced detailed information on the Axxess GMOS-044 Wiring Interface, please visit the Crutchfield website product page (/ISEO-rccbcspd/p_120GMOS044/Axxess-GMOS-044-Wiring-Interface.html ).

Searches related to the Axxess GMOS-044 Wiring Interface Connect a new car stereo and retain OnStar® and safety warning chimes in select 2011-up GM vehicles