AXXESS GMOS-MOST-02 Car Audio Amplifier Retention Interface Instruction Manual

: June 4, 2024
: AXXESS

Table of Contents

AXXESS GMOS-MOST-02 Car Audio Amplifier Retention Interface
INTERFACE FEATURES
INTERFACE COMPONENTS
APPLICATIONS
TOOLS REQUIRED
CONNECTIONS TO BE MADE
INSTALLING THE GMOS-MOST-02
- Corvette
PROGRAMMING THE GMOS-MOST-02
ADJUSTING THE GMOS-MOST-02
GMOS-MOST-02 AMPLIFIER RETNETION INTERFACE FOR GM
References
Read User Manual Online (PDF format)
Download This Manual (PDF format)

AXXESS GMOS-MOST-02 Car Audio Amplifier Retention Interface

AXXESS-GMOS-MOST-02-Car-Audio-Amplifier-Retention-Interface-
PRODUCT

INTERFACE FEATURES

Provides accessory power (12-volt 10-amp)
Retains R.A.P. (retained accessory power)
Retains OnStar / OE Bluetooth
Retains warning chimes
Provides NAV outputs (parking brake, reverse, speed sense)
Pre-wired ASWC-1 harness (ASWC-1 sold separately)
Retains the factory backup camera
Used in MOST ® amplified applications
Adjustable gain control for overall volume
High level speaker input
Retains balance
Micro “B” USB updatable

INTERFACE COMPONENTS

GMOS-MOST-02 interface
GMOST-MOST-02 harness
16-pin harness with stripped leads
Backup camera harness
10-pin jumper harness

APPLICATIONS

CHEVROLET

Corvette 2014-up Impala 2014-up

TOOLS REQUIRED

Cutting tool
Crimping tool
Tape
Connectors (example: butt-connectors, bell caps, etc.)
Small flat-blade screwdriver

CAUTION: All accessories, switches, climate control panels, and especially air bag indicator lights must be connected before cycling the ignition. Also, do not remove the factory radio with the key in the on position, or while the vehicle is running.

CONNECTIONS TO BE MADE

From the 16-pin harness with stripped leads to the aftermarket radio

Connect the Red wire to the accessory wire.
- Note: If installing an ASWC-1 (sold separately), there will be an accessory wire there to connect as well.
Connect the Blue/White wire to the amp turn on wire. This wire must be connected to hear sound from the factory amplifier.
If the aftermarket radio has an illumination wire, connect the Orange/White wire to it.
If also installing an ASWC-1 (sold separately), connect the Brown wire to the Brown wire in the 12-pin pre-wired ASWC-1 harness.
Connect the Gray wire to the right front positive speaker output.
Connect the Gray/Black wire to the right front negative speaker output.
Connect the White wire to the left front positive speaker output.
Connect the White/Black wire to the left front negative speaker output.
Connect the Green wire to the left rear positive speaker output.
Connect the Green/Black wire to the left rear negative speaker output.
Connect the Purple wire to the right rear positive speaker output.
Connect the Purple/Black wire to the right rear negative speaker output.

The following (3) wires are only for multimedia/navigation radios that require these wires

Connect the Blue/Pink wire to the VSS/speed sense wire.
Connect the Green/Purple wire to the reverse wire.
Connect the Light Green wire to the parking brake wire.

From the GMOS-MOST-02 harness to the aftermarket radio

Connect the Black wire to the ground wire.
Connect the Yellow wire to the battery wire.
Disregard the Red wire, it will not be used in this application.
Disregard the Red & White RCA jacks, they will not be used in this application.

12-pin pre-wired ASWC-1 harness

This harness is to be used along with the ASWC-1 (sold separately) to retain steering wheel audio controls. If the ASWC-1 is not being used, disregard this harness. If it will be used, please refer to the ASWC-1 instructions for radio connections and programming.
- Note: Disregard the harness that comes with the ASWC-1.
Connect the Red wire to the accessory wire.
Connect the Brown wire to the Brown wire from the 16-pin harness with stripped leads.
Connect the Green/Black wire, to the Green/Black wire in the 10-pin Black connector located in the steering column. (Figure A)

DIN jack

Disregard the DIN jack, it will not be used in this application.
- Note: The relay attached to the GMOS-MOST-02 harness is only for audible turn signal clicks. No extra steps are required to retain this feature, so leave the relay as-is.

From the backup camera harness to the aftermarket radio

If the vehicle is equipped with a factory backup camera, connect the Yellow RCA jack to the backup camera input.

INSTALLING THE GMOS-MOST-02

With the key in the off position

Locate the radio brain and Human Machine Interface module (HMI):

Corvette

Radio Brain: Passenger foot-well
HMI: Left side of dash

Impala

Radio Brain & HMI: Under the passenger side dashboard
Connect the GMOS-MOST-02 harness to the 20-pin Gray connector, and 8-pin Light Gray connector, removed from the radio brain.
Connect the backup camera harness to the 12-pin Gray connector removed from the HMI module.
Connect the 16-pin harness with stripped leads, and the GMOs-MOST-02 harness, into the GMOS-MOST-02 interface.
If the vehicle is equipped with a media player, connect the 10-pin jumper harness to the connector removed from the media player.

Note: If also installing an ASWC-1, connect it after your program and test the GMOS-MOST-02, with the key in the off position.

PROGRAMMING THE GMOS-MOST-02

Attention: If the interface loses power for any reason, the following steps will need to be performed again.

Turn the key (or push-to-start button) to the ignition position and wait until the radio comes on.
- Note: If the radio doesn’t 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, and then to the accessory position. Test all functions of the installation for proper operation, before reassembling the dash.

ADJUSTING THE GMOS-MOST-02

With the vehicle and radio turned on, turn the volume up 3/4 of the way.
Locate the end of the GMOS-MOST-02, where the 16-pin harness with stripped leads connects to.
With a small flat-blade screwdriver, adjust the potentiometer clockwise to raise the audio level; counterclockwise to lower the audio level.
Once at the desired level, audio level adjustment is complete.

IMPORTANT: If you are having difficulties with the installation of this product, please call our Tech Support line at 1-800-253-TECH. Before doing so, look over the instructions a second time, and make sure the installation was performed exactly as the instructions are stated. Please have the vehicle apart and ready to perform troubleshooting steps before calling.