Metra Electronics GMOS-04 user manual

Summary of the content on the page No. 1

GM ONSTAR CLASS II DATA BUS INTERFACE
GMOS-04
INSTALLATION INSTRUCTIONS
* READ IMPORTANT WARNING ON PAGE 1
BEFORE ATTEMPTING ANY INSTALLATION
THE GMOS-04 IS DESIGNED TO BE USED WITH VEHI-
CLES THAT HAVE A FACTORY AMPLIFIED SYSTEM
INCLUDING THE BOSE AUDIO SYSTEMS. BESIDES
RETAINING THE ONSTAR SYSTEM, THE GMOS-04 WILL
ALSO RETAIN THE WARNING CHIMES THAT WILL BE
LOST WHEN THE FACTORY RADIO IS REMOVED. THE
GMOS-04 WILL ALSO PROVIDE A 12 VOLT SWITCHED
WIRE FOR PROPER RADIO OPERATION. THE GMOS-04
NOW

Summary of the content on the page No. 2

GMOS-04 * 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 UNDER- STAND THE INSTRUCTIONS SO AS TO PROPERLY AND SAFELY COMPLETE THE INSTALLATION YOU SHOULD CONSULT A TECHNICIAN WHO DOES HAVE THIS KNOWLEDGE AND UNDERSTANDING.

Summary of the content on the page No. 3

GMOS-04 4. Connect the Green/Purple wire to the reverse wire of the aftermarket radio. APPLICATIONS IMPORTANT GMC BUICK • When completed, plug the 14 pin harness into the GMOS-04. • THE BROWN LOOP ON THE 16 PIN HARNESS MUST BE CUT THEN TAPED UP. ALLURE 2005-07 ENVOY 2002-07 PLEASE REFER TO THE ONSTAR LEVEL AJUSTMENT SECTION FOR FURTHER INSTALLING THE GMOS-04 CENTURY 2004-05 SAVANA 2003-07 DETAILS ABOUT THE BROWN WIRE. SIERRA 2003-06 RAINIER 2004-07 1. With all connections completed to the afterm

Summary of the content on the page No. 4

GMOS-04 TOUBLESHOOTING: Chime Too Loud/Soft: There are some instances where the chime is too loud or too soft. To resolve this follow these steps: 1. Make sure the ignition is turned to the “off” position. 2. Disconnect the 14 pin and 16 pin wire harnesses from the GMOS-04 3. Open up the GMOS-04 by squeezing the sides of the top cover 4. Locate the potentiometer facing up on the circuit board, this is the Chime potentiometer 5. Taking a small flat headed screwdriver, turn the potentiometer cl