User Guide

ONSTAR LEVEL ADJUSTMENT
To adjust the Onstar volume level find the Black/Yellow wire on the 16-pin har-
ness. 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 auto-
matically 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.
32
GMOS10
TOOLS REQUIRED FOR INSTALLATION
• Cutting Tool • Tape • Crimping Tool
• Connectors (ie: butt-connectors, bell caps, etc.)
4
HARNESS PREPARATION
* Important: Before beginning any of the following, disconnect the negative
battery terminal to prevent accidental short circuit.
**Note: The ignition power source of the Cadillac keeps the radio on until one
of the doors is opened. This is called the R.A.P. (retained accessory power).
The GMOS-10 is designed to retain this feature.
Connections to be made on the 14 pin harness:
1) Connect the white RCA to the radio’s left front RCA output.
2) Connect the gray RCA to the radio’s right front RCA output.
3) Connect the green RCA to the radio’s left rear RCA output.
4) Connect the violet RCA to the radio’s right rear RCA output.
Note: If no RCA outputs are available, use the Metra line output converter
part # LOC-648 (sold separately).
5) Connect the blue/white wire to the radio’s amplifier turn-on output.
6) Connect the red wire to the radio’s 12-volt accessory or switched wire.
The following wires on the 14-pin harness are for the aftermarket radios
equipped with navigation features:
1) Connect the Brown wire to the mute wire of the aftermarket radio.
2) Connect the Green wire to the parking brake wire of the aftermarket radio.
3) Connect the Blue/Pink wire to the VSS or speed sense wire of the
aftermarket radio.
4) Connect the Green/Purple wire to the reverse wire of the aftermarket radio.
When completed,
plug the 14-pin harness into the GMOS-10.
Connections to be made on the 16 pin harness:
1) Connect the yellow wire to the radio’s 12-volt battery or memory wire.
2) The blue/white wire is the amplifier turn-on wire for aftermarket amplifiers
only. If you are not using this connection, be sure to properly terminate the
wire using an insulated connector or electrical tape.
3) The black/yellow wire will be discussed in the Onstar Level Adjustment
section.
When completed, plug the 16-pin harness into the GMOS-10.
INSTALLING THE GMOS-10
1) With all connections completed to the aftermarket radio, plug the 16 and
20 pin harness into the Cadillac’s wiring harness.
2) Cycle the key by turning the ignition on then back off, then on again to test
the radio.
TESTING THE GMOS-10
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.
AUDIO LEVEL ADJUSTMENT
When using the GMOS-10 with a radio that has a high pre-out voltage the audio
signal may become distorted.
To resolve this follow these steps:
1. Locate the potentiometer next to the 14-pin connector
located on the GMOS-10.
2. Taking a small flat headed screwdriver, turn the potentiometer
counter-clockwise to lower the input level going to the factory amplifier.
Note: The chime volume will also adjust with the audio input.