Axxess GMOS-04 User manual

METRA. THE WORLD’S BEST KITS.™
© COPYRIGHT 2004-2011 METRA ELECTRONICS CORPORATION
1-800-221-0932 metraonline.com
INSTALLATION INSTRUCTIONS FOR PART INSTGMOS-04
REV. 12/21/11
• Cutting tool • Crimping tool • Tape • Connectors (butt-connectors, bell caps, etc.)
IGNITION TERMINALS
WIRE CUTTER
M3.5
M2.6
M3
M5
M4
ISO
6
2.5
1.5
TOOLS REQUIRED
GM amplified OnStar Class II Data Bus
Interface 2000-up
GMOS-04
GMOS-04 interface • 16-pin harness with stripped leads
18-pin harness to 12- and 24-pin GM harness with stripped leads
INTERFACE COMPONENTS
KIT FEATURES
APPLICATIONS
• Provides accessory (12-volt 10-amp)
• Retains R.A.P. (Retained Accessory Power)
• Used in amplified systems
• Retains chimes
• Provides NAV outputs (Parking Brake, Reverse, Mute, V.S.S.)
• ASWC harness included (ASWC not included)
• Retains OnStar/OE Bluetooth
• Adjustable volume for chimes and OnStar
• High level speaker input
• USB updatable
• Retains balance and fade
See inside front cover

Applications
GMOS-04
Caution: Metra recommends disconnecting the negative battery terminal before beginning
any installation. All accessories, switches, and especially air bag indicator lights must be
plugged in before reconnecting the battery or cycling the ignition.
*NOTE: Refer also to the instructions included with the aftermarket radio.
BUICK
Allure 2005-2009
Century 2004-2005
LaCrosse 2005-2009
Rainer 2004-2007
Rendezvous 2002-2007
Terraza 2005-2008
CADILLAC
Escalade 2003-2006
Escalade EXT 2003-2006
CHEVROLET
Avalanche 2003-2006
Cavalier 2000-2005
Colorado 2004-up
Corvette 2005-up
Express 2003-2007
Impala 2000-2005
Malibu 2000-2003
Malibu Classic 2004
Monte Carlo 2000-2005
Silverado 2003-2006
Silverado Classic 2007
SSR 2003-2006
Suburban 2003-2006
Tahoe 2003-2006
Trailblazer 2002-2009
Uplander 2005-2008
Venture 2000-2005
GMC
Canyon 2004-up
Envoy 2002-2009
Savana 2003-2007
Sierra 2003-2006
Sierra Classic 2007
Yukon/XL/Denali 2003-2006
HUMMER
H2 2003-2007
H3 2006-2009
ISUZU
Ascender 2003-2008
I-Series 2006-2008
OLDSMOBILE
Alero 2001-2004
Bravada 2002-2005
Intrigue 2002
Silhouette 2000-2004
PONTIAC
Aztec 2001-2005
Grand Am 2001-2005
Grand Prix 2004-2008
Montana 2000-2005
Sunfire 2000-2005
SAAB
9-7x 2005-2009
SATURN
Relay 2005-2007
(Note: This interface will also work in vehicles listed below that are not equipped with OnStar)

From the 16-pin harness:
• Connect the Red wires to the ignition wire of the aftermarket radio.
• Connect the Orange/White wire to the illumination wire of the aftermarket radio. If the
aftermarket radio has no illumination wire just tape off the Orange/White wire.
• Connect the White wire to the left front positive speaker output of the aftermarket radio.
• Connect the White/Black wire to the left front negative speaker output of the
aftermarket radio.
• Connect the Gray wire to the right front positive speaker output of the aftermarket radio.
• Connect the Gray/Black wire to the right front negative speaker output of the
aftermarket radio.
• Connect the Green wire to the radio’s left rear positive speaker output.
• Connect the Green/Black wire to the radio’s left rear negative speaker output.
• Connect the Purple wire to the radio’s right rear positive speaker output.
• Connect the Purple/Black wire to the radio’s right rear negative speaker output.
• Connect the Blue/White wire to the radio’s amp turn on wire.
• Connect the Brown wire to the mute wire of the aftermarket radio. If the aftermarket
radio does not have a Mute wire, tape up the Brown wire.
• Connect the Light Green wire to the parking brake wire of the aftermarket
navigation radio.
• Connect the Blue/Pink wire to the VSS or speed sense wire of the aftermarket
navigation radio.
• Connect the Green/Purple wire to the reverse wire of the aftermarket navigation radio.
• Plug the 16-pin harness into the GMOS-04.
3
Connections to be made
GMOS-04

4
GMOS-04
From the 24-pin harness:
• Connect the Yellow wire to the radio’s 12-volt battery or memory wire.
• Connect the Black wire to the radio’s ground wire.
• Plug the 14-pin harness into the GMOS-04.
• The Black/Yellow wire is for the OnStar volume adjustment. This will be discussed in
the OnStar Level Adjustment section of this instruction.
The 12-pin harness (ASWC plug) will be discussed later in the manual.
Connections to be made
Connections to be made
For 2005-up Corvette only (Figure A):
• A relay is needed in the 2005-up Corvette. You will need to cut the Blue/White wire in
half between the 18-way Molex and 24-way Gray connector.
• Connect the Blue/White wire coming from the 18-way Molex to pin 85 of the relay.
• Connect the Blue/White wire coming from the 24-way connector to pin 30 of the relay.
• Connect pin 86 of the relay to ground.
• Connect pin 87 of the relay to fused 12-volt constant wire. Using tape or a wire, tie
securely the relay from moving around the dash.
• When completed, plug the 18-pin harness into the GMOS-04.

5
GMOS-04
To Vehicle
To Radio
+12v Battery
Fused 5A
SPDT
relay
GMOS-04
87
87a 8685
30
12v remote from
GMOS-04
Blue/White
Cut remote out from GMOS-04.
Connect interface side to
pin 85 on SPDT relay.
(Figure A)
• With all connections completed to the aftermarket radio, plug the 24- and 12-pin
harnesses into the vehicles wiring harnesses.
• Reconnect the negative battery terminal.
• Cycle the key, by turning the ignition on for 30 seconds. Then off and on again
to test the radio.
Installing the GMOS-04

6
GMOS-04
1) Turn the ignition on if not already, and then turn the radio on to verify that the radio
works. Check balance and fader controls for proper operation.
2) Push the OnStar button (if equipped) to verify OnStar is working. The radio will shut off or
mute, depending if the Brown wire on the 16-pin harness is connected, and OnStar will
be heard through the front speakers. Turn off OnStar and the radio will turn back on.
Chime Volume Adjustment
Note: If Y91 is present on the RPO list, refer to your owner’s manual to adjust chimes.
1) With car on, shut off car and leave keys in ignition. Open
the car door and leave it open. Chimes will be heard.
2) Wait 10 seconds, then with a small screwdriver adjust
the potentiometer fully counterclockwise (all the way left),
then clockwise to raise chime level and counterclockwise
to lower the chime level.
3) When the volume is at the desired level, remove the keys
from the ignition. This will lock the chime volume at its
current level.
Audio Level Adjustment
1) Start your vehicle and turn on the radio having audio playing.
2) Turn your aftermarket radio’s volume up ¾ of the way.
3) With a small screwdriver adjust the potentiometer clockwise to raise the audio level and
counterclockwise to lower the audio level.
4) Once at desired level your audio adjustment is complete.
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, the customer may also tap volume up or down on the steering wheel (if equipped)
to adjust the OnStar level.
Testing the GMOS-04
Potentiometer located on 16 pin
side of the interface

GMOS-04
7
Additional 12-pin harness (ASWC harness)
* For the following vehicles please cut the White/Green, Green/Orange, and Orange/Green wires before programming the ASWC.
** For the following vehicles please cut the White/Green, Pink, and Orange/Green wires before programming the ASWC.
*** For the following vehicles please cut the Pink and Orange/Green wires before programming the ASWC.
**** For the following vehicles please cut the White/Green and Pink wires before programming the ASWC.
***** For the following vehicles please cut the Pink wire before programming the ASWC.
This 12 pin harness is to be used in conjunction with the ASWC (not included).
Please refer to ASWC instructions for programming.
BUICK
*****Allure 2005-2009
****Century 2004-2005
****LaCrosse 2005-2009
*Rainer 2004-2007
*****Rendezvous 2002-2007
*****Terraza 2005-2008
CADILLAC
*Escalade 2003-2006
*Escalade EXT 2003-2006
CHEVROLET
*Avalanche 2003-2006
*Cavalier 2000-2005
*Colorado 2004-up
***Corvette 2005-up
**Impala 2000-2005
Malibu 2000-2003
Malibu Classic 2004
**Monte Carlo 2000-2005
*Silverado 2003-2006
*Silverado Classic 2007
*SSR 2003-2006
*Suburban 2003-2006
*Tahoe 2003-2006
*Trailblazer 2002-2009
**Uplander 2005-2008
**Venture 2000-2005
GMC
*Canyon 2004-up
*Envoy 2002-2009
*Sierra 2003-2006
*Sierra Classic 2007
*Yukon/XL/Denali 2003-2006
HUMMER
*H2 2003-2007
*H3 2006-2009
ISUZU
*Ascender 2003-2008
*I-Series 2006-2008
OLDSMOBILE
**Alero 2001-2004
*Bravada 2002-2005
**Intrigue 2002
**Silhouette 2000-2004
PONTIAC
**Aztec 2001-2005
**Grand Am 2001-2005
**Grand Prix 2004-2008
**Montana 2000-2005
*Sunfire 2000-2005
SAAB
*9-7x 2005-2009
SATURN
**Relay 2005-2007

METRA. THE WORLD’S BEST KITS.™
© COPYRIGHT 2004-2011 METRA ELECTRONICS CORPORATION
1-800-221-0932 metraonline.com
INSTALLATION INSTRUCTIONS FOR PART INSTGMOS-04
REV. 12/21/11
KNOWLEDGE IS POWER
Enhance your installation and fabrication skills by
enrolling in the most recognized and respected
mobile electronics school in our industry.
Log onto www.installerinstitute.com or call
800-354-6782 for more information and take steps
toward a better tomorrow.
Metra recommends MECP
certified technicians
IMPORTANT WARNING
This product includes instructions for installation which must be carefully
followed. The instructions are worded in such a manner to assume
that the installer is capable of completing these type of electronic
installations. If you are unclear as to what you are instructed to do or
believe that you do not understand the instructions so as to properly and
safely complete the installation you should consult a technician who
does have this knowledge and understanding.
Failure to follow these instructions carefully and to install the
interface as described could cause harm to the vehicle or to safety
systems on the vehicle. Interference with certain safety systems
could cause harm to persons as well. If you have any questions in
this regard please call the Help line or Metra at
1-800-221-0932 for assistance.

METRA. THE WORLD’S BEST KITS.™
© COPYRIGHT 2004-2011 METRA ELECTRONICS CORPORATION
1-800-221-0932 metraonline.com
INSTRUCCIONES DE INSTALACIÓN PARA LA PIEZA INSTGMOS-04
REV. 12/21/11
• Herramienta de corte • Cinta • Herramienta engarzadora
• Conectores (p. ej., conectores a tope, tapas acampanadas, etc.)
IGNITION TERMINALS
WIRE CUTTER
M3.5
M2.6
M3
M5
M4
ISO
6
2.5
1.5
HERRAMIENTAS REQUERIDAS
Interfaz de bus de datos Clase II OnStar
no amplificado para gm 2000 y mas
GMOS-04
Interfaz GMOS-04 • Arnés de 16 pines con conectores pelados
Arnés de 14 pins a arnés GM de 12 y 24 pins con conectores pelados
COMPONENTES DEL KIT
CARACTERÍSTICAS DEL KIT
APLICACIONES
• Proporciona accesorio (12 voltios 10 amperes)
• Retiene R.A.P. (Corriente de accesorio retenida)
• Usado en reemplazan los sistemas amplificados
• Retiene los tonos
• Proporciona salidas de NAV (freno de mano, reversa, silencio, V.S.S.)
• Arnés de ASWC incluido (ASWC no incluido)
• Retiene el bluetooth OE/OnStar
• Volumen ajustable para tonos y OnStar
• Entrada de bocina de alto nivel
• Adaptable a USB
• Retiene el balance y la intensidad
Vea la lista de aplicaciones en el interior

Aplicaciones
GMOS-04
PRECAUCIÓN: Metra recomienda desconectar el terminal negativo de la batería antes de
comenzar cualquier instalación. Todos los accesorios, interruptores y, especialmente, las
luces indicadoras de airbag deben estar enchufados antes de volver a conectar la batería o
comenzar el ciclo de ignición.
Nota: Remítase a las instrucciones incluidas con el radio de postventa.
BUICK
Allure 2005-2009
Century 2004-2005
LaCrosse 2005-2009
Rainer 2004-2007
Rendezvous 2002-2007
Terraza 2005-2008
CADILLAC
Escalade 2003-2006
Escalade EXT 2003-2006
CHEVROLET
Avalanche 2003-2006
Cavalier 2000-2005
Colorado 2004 y mas
Corvette 2005 y mas
Express 2003-2007
Impala 2000-2005
Malibu 2000-2003
Malibu Classic 2004
Monte Carlo 2000-2005
Silverado 2003-2006
Silverado Classic 2007
SSR 2003-2006
Suburban 2003-2006
Tahoe 2003-2006
Trailblazer 2002-2009
Uplander 2005-2008
Venture 2000-2005
GMC
Canyon 2004 y mas
Envoy 2002-2009
Savana 2003-2007
Sierra 2003-2006
Sierra Classic 2007
Yukon/XL/Denali 2003-2006
HUMMER
H2 2003-2007
H3 2006-2009
ISUZU
Ascender 2003-2008
I-Series 2006-2008
OLDSMOBILE
Alero 2001-2004
Bravada 2002-2005
Intrigue 2002
Silhouette 2000-2004
PONTIAC
Aztec 2001-2005
Grand Am 2001-2005
Grand Prix 2004-2008
Montana 2000-2005
Sunfire 2000-2005
SAAB
9-7x 2005-2009
SATURN
Relay 2005-2007
(Nota: Esta interfaz también funcionará en los vehículos enumerados a continuación
que no están equipados con OnStar)