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Adapter Features
Class II Harness
GMLAN 11 Harness
GMLAN 29 Harness
Installation Notes

Adapter Features

Overview: The GMOS-100 is a GM all-in-one solution to add an aftermarket radio to select 2000-up GM vehicles with the CLASS II, GMLAN 11, or GMLAN 29 bit data systems. The GMOS-100 can be used to retain your factory amplifier, OnStar, Bluetooth, Satellite Radio (factory D.I.C. or optional LCD required), steering wheel controls, rear-seat entertainment (GMLAN 29 harness only; depending on type of vehicle), and factory backup camera (GMLAN 29 harness only; depending on type of vehicle). In addition, all the warning chimes and convenience features are retained that are normally lost when the OEM radio is removed. The GMOS-100 also provides a 12-volt/10-amp accessory output and connections to help install a navigation radio which include VSS, Parking Brake, and Reverse (rear-view camera).

Note: There are three types of GM harness included (CLASS II, GMLAN 11 bit, and GMLAN 29 bit). Only one will be used for your specific vehicle. Please consult Crutchfield's Outfit My Car to see if your vehicle is compatible and what additional accessories will be needed.

Class II Harness

Class II Harness Compatibility Chart: The included Class II harness is compatible with the following 2000-up Buick, Cadillac, Chevrolet, GMC, Hummer, Isuzu, Oldsmobile, Pontiac, Saab, and Saturn vehicles (as of October 2012):

Class II Harness Feature Set:

• 10-Amp ACC 12v output
• Retains all factory warning chimes
• Retains OnStar *
• Retains factory amp *
• Retains Steering Wheel Controls *
• Retains factory Bluetooth *
• Retains factory Satellite Radio (RCA AUX input and separate XIA-LCD required)
• Provides Navigation outputs (VSS, Park Brake, Reverse signal)

Note: *If equipped

GMLAN 11 Harness

GMLAN 11 Harness Compatibility Chart: The included GMLAN II harness is compatible with the following Chevrolet, Pontiac, and Saturn vehicles (as of October 2012):

GM 11-Bit LAN Harness Feature Set:

• 10-Amp ACC 12v output
• Retains all factory warning chimes
• Retains turn signal indicators via pre-wired relay
• Retains OnStar *
• Retains factory amp *
• Retains Steering Wheel Controls *
• Retains factory Bluetooth *
• Retains factory Satellite Radio (RCA AUX input and separate XIA-LCD required)
• Provides Navigation outputs (VSS, Park Brake, Reverse signal)

Note: *If equipped

GMLAN 29 Harness

GMLAN 29 Harness Compatibility Chart: The included GMLAN 29 harness is compatible with the following 2006-up Buick, Cadillac, Chevrolet, GMC, Hummer, Pontiac, Saturn, and Suzuki vehicles (as of October 2012):

GM 29-Bit LAN Harness Feature Set:

• 10-Amp ACC 12v output
• Retains all factory warning chimes
• Retains turn signal indicators via pre-wired relay
• Retains factory backup cam (video unit with rear cam RCA input required)
• Retains Rear Seat Entertainment (RCA AUX input required)
• Retains OnStar *
• Retains factory amp *
• Retains Steering Wheel Controls *
• Retains factory Bluetooth *
• Retains factory Satellite Radio (RCA AUX input required, D.I.C. and factory SWC required, otherwise XIA-LCD must be used)
• Provides Navigation outputs (VSS, Park Brake, Reverse signal)

Note: *If equipped

Installation Notes

Satellite Radio Note: Your factory Satellite Radio information will continue to be displayed through your vehicle's factory Driver Information Center (D.I.C.). This factory D.I.C. is not removed when replacing your factory radio with your new aftermarket head unit. If your vehicle is not equipped with a separate Driver Information Center and the factory radio displays all Satellite Radio information, you will lose Satellite Radio text, unless you purchase the XIA-LCD (120XIALCD, sold separately), which provides a separate LCD screen from your new aftermarket stereo and allows you to navigate through factory installed Satellite Radio options.

Note: Vehicles that require the GMLAN29 harness still allow you to control your factory Satellite Radio through your vehicle's factory steering wheel controls, even without the Driver Information Center; but you will lose text display.

OEM Steering Wheel Control Compatible: The GMOS-100 features a 3.5mm connector that lets you keep your GM vehicle's OEM steering wheel controls when installing a compatible aftermarket radio.

Level Adjustments: The GMOS-100 provides chime/turn signal volume adjustment, overall gain level adjustment, and OnStar level adjustment.

• Chime/Turn Signal Volume Adjustment: To adjust the chime volume, use a small screwdriver to rotate the module's potentiometer (located on the 8-pin harness side of the interface; closest to 8-pin harness). Turn clockwise to make the chime/turn signal louder and counterclockwise to make the chime/turn signal softer. Turn signal will not be affected in non-amplified or class II systems.
• Overall Gain Level Adjustment: To adjust the overall audio volume of your vehicle, use a small screwdriver to rotate the potentiometer, located on the 8-pin harness side; furthest away from 8-pin harness). Turn clockwise to make gain louder and counterclockwise to make the gain softer.
• OnStar Level Adjustment: To adjust the OnStar volume level, find the Black/Yellow wire on the 20-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.

RSE/Backup Camera Note: The GMOS-100 only retains factory RSE (rear seat entertainment) and backup camera in select vehicle's which require the GMLAN29.