Installing the GMOS-13
With the key in the off position:
• Connect the 16-pin harness with stripped leads, and the GMOS-13 harness, into
the interface.
• Connect the GMOS-13 harness to the wiring harness in the vehicle.
Note: If using the ASWC-1, connect it after you initialize and test the GMOS-13,
with the key in the off position.
Initializing the GMOS-13
Attention! If the interface loses power for any reason, the following steps will need
to be performed again. Also, if installing an ASWC-1, connect it after you initialize
and test the interface/radio, with the key in the off position.
• Turn the key (or push-to-start button) to the ignition position and wait until the
radio comes on.
Note: If the radio does not come on within 60 seconds, turn the key to the
off position, disconnect the interface, check all connections, reconnect the
interface, and then try again.
• Turn the key to the off position, pause for a moment, and then to the accessory
position. Test all functions of the installation for proper operation, before
reassembling the dash.
®
GMOS-13
Adjusting the GMOS-13
Audio level adjustment:
• With the vehicle and radio turned on, turn the volume up 3/4 of the way.
• With a small flat-blade screwdriver, adjust the potentiometer clockwise to
raise the audio level; counterclockwise to lower the audio level.
• Once at a desired level, audio level adjustment is complete.
Chime level adjustment:
• Refer to the vehicle owner's manual to adjust the chimes.
OnStar Level Adjustment:
• Press the OnStar button to activate it.
• While OnStar is speaking, press the VOLUME UP or VOLUME DOWN button on
the steering wheel to raise or lower the OnStar level.
• If the vehicle does not come equipped with steering wheel controls, or they no
longer function, locate the Black/Yellow wire on the GMOS-13 harness.
• While OnStar is speaking, tap the Black/Yellow wire to ground. Once the
OnStar level is set, it will stay at that level until the Black/Yellow wire is
tapped to ground again.
3