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PAC OS-1 Wiring Interface
Connect a new car stereo and retain OnStar® in select GM vehicles
Our take on the PAC OS-1 Wiring Interface
PAC's OS-1 interface lets you replace any General Motors radio (without RDS) while maintaining operation of the OnStar® system. The OS-1 has on-board switching and built-in amplification that allows audio from the OnStar® system to play through the two front factory speakers 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. 1-year warranty.
Note: The OS-1 will interface with all GM radios that do NOT have the "RDS" option — it works with Bose and standard GM radios. If there is an "RDS" logo on the radio face, the OS-1 will not work.
Note: Most vehicles will require additional installation parts please identify your vehicle if you haven’t done so. You can also call an Advisor for more information.
Works as advertised - all the wire colors match and it's an easy connection to the head unit. Fit easily behind the vent controls in my 2002 Yukon (Tahoe) Note that you don't need the other harness adapter if you use the PAC
CodyT, Tucson, AZ
What's in the Box:
- 1 GM OnStar Interface adapter with 7" OS-GM9 Molex plug and a 44" ground wire
- One 12" OS-1618 harness
- One 6.5" OS-RAD harness
- One 6" OS-GM21 harness
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Applications: The OS-1 is an interface that allows for the replacement of a GM factory radio that doesn't have RDS, while maintaining the operation of the OnStar navigational system. The OS-1 has onboard 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.
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.
Harnesses: The harnesses allow the OS-1 to be installed in either a Bose or Non-Bose factory system. Refer to the instructions for specific information on wiring configuration for your particular application.
Inputs/Outputs: On the left side of the adapter, there is an 18-Pin Male Molex plug. On the right side of the adapter, there is a 16-Pin Male Molex plug, and there is a 7" harness with a 9-Pin OS-GM21 connector. Refer to the instructions for specific information on wiring configuration for your particular application.
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