Onstar GMOS06 Installation Instructions

INSTALLING THE GMOS-06
1)With all connections completed to the aftermarket radio, plug the 32 pin harness into the Cadillac’s wiring harness.
*Note: some minor modifications may be necessary to the sub dash cavity to accommodate the GMOS-06.
2) Cycle the key by turning the ignition on then back off, then on again to test the radio.

TESTING THE GMOS-06
1) Turn the ignition on, then turn the radio on to verify that the radio works. Check the balance control of the radio for proper operation.
2) Push the Onstar button, if so equipped, to verify Onstar is working properly. The radio will turn off or mute if the radio has this feature and Onstar will be heard through the front speakers. Turn off Onstar and the radio will turn back on or deactivate mute if equipped.

ONSTAR LEVEL ADJUSTMENT
To adjust the Onstar volume level find the Black/Yellow wire on the 16-pin harness. Push the blue Onstar button, while the voice is speaking tap the Black/Yellow wire to ground. There are 4 volume settings for Onstar; once the 4th setting is reached and the Black/Yellow wire is tapped to ground it will automatically go back to the first volume setting. Once the volume is set it will stay at that volume until the Black/Yellow wire is tapped to ground again. This can be set during installation and then left alone. If user adjustment is desired, a momentary contact switch (sold separately) can be added. Connect one terminal from the switch to ground and the other terminal to the Black/Yellow wire. The volume will change one level every time the switch is pressed.

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