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.
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.
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
Metra GMOS-04 Wiring Interface reviews
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More details on the Metra GMOS-04 Wiring Interface
Radio Replacement Interface: 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.
Note: Radio information through the factory HUD (Heads-Up Dispaly) will be lost after installing an aftermarket radio, but vehicle information will still be retained.
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.
The Metra GMOS-04 Wiring Interface replaces these items
Retains ONSTAR system, factory door chime, and Bose system with aftermarket radio
- Lets you install an aftermarket receiver in late model GM vehicles without losing the door chime and audible safety warnings, the Bose amplified speakers, or the ONSTAR system
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