Radio Replacement and Steering Wheel Control Interface
SWC Connection
See above chart for
different radio type
connections
x3
XM R
XM L
GM3A-RSTX
with OnStar Retention for General Motors Vehicles
Introduction and Features
The GM3A-RSTX interface allows the replacement of a factory radio in select General Motors vehicles with 29-bit LAN
radios. Using this interface will retain factory features such as OnStar, steering wheel controls (SWC), warning chimes,
Rear Seat Controls (RSC), factory XM Radio and the BOSE amplier when the original radio is removed. Use of this
interface also allows you to program two radio functions to each SWC button by using short press long press dual
command functionality. The GM3A-RSTX also provides data bus driven outputs such as retained accessory power
(RAP), vehicle speed signal (VSS), illumination, reverse trigger and parking brake.
Important Notes
1. These instructions only apply to R.2.6.6.19 or later revisions. The revision info can be found on a small white sticker on the
interface and packaging.
2. The radio select rotary switch on the side of the interface must be adjusted to the proper radio setting before plugging the
interface into the vehicle (see next page for setting chart).
3. The interface comes pre-programmed for all of the vehicles factory SWC functions and does not require programming unless
you wish to re-assign the SWC functions or utilize short press long press dual command functionality. The SWC can always be
restored to default settings by following the procedure outlined on page 2.
4. RSC buttons that are identical to the SWC will mimic the SWC one for one.
5. The LED will ash whenever a SWC button is pressed.
Wiring Connection Chart
Aftermarket Radio Connections
Yellow *+12v from RP Advanced
Yellow *+12v from vehicle
Black **Ground from RP Advanced
Black **Ground from vehicle
RedAcc. Output
WhiteFront Left + input
White / BlackFront Left - input
GreyFront Right + input
Grey / BlackFront Right - input
GreenRear Left + input
Green / BlackRear Left - input
PurpleRear Right + input
Purple / BlackRear Right - input
Illustration / Schematic
WiringSWC Connection
Power and speaker
connections
SWC Connector
Light GreenParking Brake Output (-)
PinkVehicle Speed Output
BlueNot Used
Blue / WhiteAmp Turn On Input
Orange / WhiteIllumination Output (+)
Purple / WhiteReverse Output (+)
Brown Loop
IMPORTANT NOTES REGARDING YELLOW AND BLACK WIRE CONNECTIONS
* Connect both Yellow wires from the RP Advanced harnesses to the radio’s 12v
constant input
** Connect both Black wires from the RP Advanced harnesses to the radio’s ground
input.
1. The radio select rotary switch on the side of the interface must be adjusted to the proper radio
setting before plugging the interface into the vehicle.
2. Make all connections as described in the chart on page 1. Be sure to connect both Yellow wires (one from vehicle harness and one from RP
Advanced harness) and both Black wires (one from vehicle harness and one from RP Advanced harness) while making these connections.
3. Factory installed ampliers will determine the audio output connection. If the vehicle has a factory installed amplier, use the factory
amplier audio location. If a factory installed amplier is not present, use the non-amplied factory audio location.
4. If the vehicle is equipped with a Premium BOSE system, connect the subwoofer and center channel RCA inputs to the aftermarket radio. If
the aftermarket radio to be installed does not have a dedicated center channel or sub output, do not use this cable. To ensure best sound
performance, channel summing is not recommended. Use this cable according to the outputs that are available.
5. If the vehicle is equipped with a reverse camera and the aftermarket radio has a reverse camera input, connect the Yellow RCA plug on the
Brown connector to the aftermarket radio’s reverse camera input.
6. If the aftermarket radio is equipped with an auxiliary input and you wish to retain the factory XM tuner, plug the RCA connectors from the
interface into the radio’s auxiliary input.
7. Plug the CMX chime module in if necessary (If the vehicle chimes when the radio is removed, the CMX is not necessary). PLEASE NOTE:
In order to get the best possible sound out of the CMX, please mount it in a place free and clear of any obstructions, preferably as close as
possible to the bottom of the dash pointing down toward the oor of the vehicle.
8. The Mute loop (if not cut) will turn the accessory output off when an OnStar or Bluetooth call is made or received. If the aftermarket radio
has a mute input cut this loop and connect the inner Brown wire (next to the Blue / White wire) to the mute input.
9. Connect the SWC wire according to the chart on page 1 (aftermarket radio MUST support a wired remote input).
10. If you wish to reassign functions to the SWC follow the programming instructions in the next section.
Default Steering Wheel Control Programming
IMPORTANT! The interface comes pre-programmed for the functions listed in the chart below and does not require programming
unless you wish to re-assign the SWC functions, or utilize short press long press dual command functionality. The SWC can
always be restored to default settings by pressing the program button on the side of the interface once and waiting for the timeout.
Default SWC Button Assignments
Optional Steering Wheel Control Programming
If you wish to re-assign the SWC functions, utilize short press long press dual command functionality or select between Factory/
Aftermarket mode, the interface must be programmed in the specic order shown in the chart on page 4. If you come across a
function in the chart that your steering wheel does not have, or you do not want to program, press and release the program button
on the side of the interface to skip that function. The LED will ash off and on conrming that you have successfully skipped that
function and are ready to proceed to the next one.
Radio Replacement and Steering Wheel Control Interface
1
2
3
4
5
6
7
8
9
0
GM3A-RSTX
with OnStar Retention for General Motors Vehicles
Optional Steering Wheel Control Programming (cont.)
SET RADIO SELECT SWITCH
AlpineJVC
1234789
*Other - Dual / Axxera, Jensen, Rockford Fosgate
The Mute and Source buttons long press commands can be set to control the factory OnStar / XM functions or given the ability
to control the aftermarket radio. This option can be set using the program button on the side of the interface. The default setting
for these buttons is factory mode which controls the factory OnStar and XM tuner. If these buttons are set to aftermarket mode,
OnStar must be accessed by using the factory controls located on the rearview mirror, and the factory XM tuner can no longer be
accessed.
Kenwood /
Lightning Audio
Clarion /
Nakamichi
Pioneer /
Other*
SonyFusion
Factory Mode
• The SWC Mute and Source buttons are programmed
to control OnStar and Factory XM. They cannot be
programmed for short press / long press dual command
functionality and are blocked from doing so.
• Preset right button can be programmed for dual commands.
However, when XM Control is on, radio commands are
disabled temporarily. The Preset right button will control
XM preset up.
• When XM control is off the Preset right button will send
radio commands as normal.
Use the function chart on the next page as a guide to program the functions in the proper order for your new radio
1. Turn the key to the ignition position.
2. Press and release the programming button on the side of the interface the number of times that corresponds with either
factory or aftermarket mode. One press will set factory mode and two presses will set aftermarket mode. The LED will blink
each time the button is pressed.
3. Once you have chosen either factory or aftermarket mode, after 2.5 seconds the LED will come on solid. At this point you
have two options:
A. To restore the SWC to factory default settings: Simply wait 7 seconds and the LED will blink 3 times indicating
the interface has timed out. The default settings are now restored and no further action is required.
B. To program custom SWC assignments: Proceed to step 4
4. With the LED on, press the rst button to be learned on the steering wheel, the LED will turn off.At this point you have
two options:
A. For short press functionality: Release the button within 1.5 seconds. The LED will turn back on.
B. For long press functionality: Hold the button until the LED starts blinking. Release the button and the LED
will go back to solid.
5. If you need to program more buttons, repeat step 3 for each additional audio function on the steering wheel.
6. If you come across a function in the chart that your steering wheel does not have, or you do not want to program, press and
release the program button on the side of the interface to skip that function.
7. Once programming is completed, wait seven seconds. The LED will ash three times indicating end of programming.
8. Test the interface for proper functionality. Whenever a SWC is pressed the LED on the interface should blink. If any function
does not work, repeat the programming steps.
• OnStar control through the SWC Mute button is disabled.
This will free up the Mute button to send mute radio
command and a second function.
• In order to program the Source button for short press / long
press in vehicles with external XM tuner, you must unplug
the XM tuner.
Optional Steering Wheel Control Programming (cont.)
Optional Programming Order
Testing and Verication
1. Turn the ignition on. The LED on the interface will turn on and the +12v accessory wire will turn on.
2. Turn on the radio and check balance and fade. Note: Premium factory amplied systems will not fade as neither the
aftermarket radio, or the RP Advanced interface have the ability to control the amplier’s fader.
3. Verify that the factory subwoofer (if present) is playing.
4. Verify that all SWC are functioning properly for both the aftermarket radio and OnStar. To adjust OnStar volume, press the
OnStar button on the mirror, then use the volume buttons on the SWC to adjust the level. The volume will raise a total of 8
times before returning to the original level.
5. Verify that the factory XM tuner is functioning properly.
6. Pressing the OnStar button on the rearview mirror will turn off the rear speakers and allow the OnStar audio to be heard in
the two front speakers. The OnStar active LED will also turn on. When OnStar disconnects, the radio will un-mute or turn
back on and the OnStar LED will turn off. Pressing the Mute / OnStar button on the steering wheel for 1.5 seconds will also
activate OnStar.
7. Turn off vehicle and remove key. RAP will be active and keep the radio on for 10 minutes, or until the driver’s door is
opened.
8. The LED and radio will turn off when RAP turns off or the driver’s door is opened.
9. Use the 4-position selector switch located on the side of the CMX module to select the best chime output volume for your
specic installation. Setting 1 being loudest and 4 softest.
Radio Replacement and Steering Wheel Control Interface
SRCE
Press & release to
recall a preset.
Press & hold to store
a preset.
Moves back
through the XM
channels
Moves forward
through the XM
channels
Press & hold to
enable XM controls.
Press & release to
disable XM controls
Factory XM Controls
Volume Up
Volume Down
Turns the
Rear Seat
Controls On
or Off
Change between
Factory XM tuner
and Dual Zone
Radio Source
Scrolls through
Presets 1-6
Seek to the
Next
Factory XM
Tuner Station
Seek to the
Previous
Factory XM
Tuner Station
Turns the
Rear Seat
Controls On
or Off
Change between
Factory XM tuner
and Dual Zone
Radio Source
Controls the
Radio as
Programmed
by the SWC
interface (Mapped
to the Arrow
and Bar Button)
Controls the
Radio as
Programmed
by the SWC
interface (Mapped
to the Arrow
Down Button)
Controls the
Radio as
Programmed
by the SWC
interface (Mapped
to the Arrow
Up Button)
GM3A-RSTX
with OnStar Retention for General Motors Vehicles
Using Rear Seat Audio Controls
Using the Radios Dual Zone SourceUsing the Factory XM Radio Tuner
Radio
• Press the power button to turn the RSE Controls on. When
Radio is displayed on the RSE Controls, the aftermarket
radios rear speaker output will be heard through the
headphone jacks. Putting the aftermarket radio into dual
zone mode should change the output level of the rear
speakers to a xed level. This allows precise user
adjustment from the level knobs on the RSE Controls (refer
to aftermarket radio owners manual for model specic dual
zone operation).
• The seek arrows and PROG button will control the radio
as programmed by the SWC interface. These buttons are
mapped to the SWC buttons as stated above.
• Pressing the SRCE button will toggle between the Factory
XM tuner and the Radio as the RSE source. Pressing the
power button will turn the RSE Controls off as well as turning
the key off. The seek arrows and PROG button will continue
to operate as stated (with the exception of SRCE which has
no function) when the Rear Seat Controls are turned off.
XM
• Press the power button to turn the RSE Controls on. If Radio
is displayed press the SRCE button to select factory XM
tuner mode. When XM followed by the channel number is
displayed factory XM tuner audio will be heard through the
headphone jacks.
• The Seek arrows will control the factory XM radio tuner and
select the desired station.
• The PROG button will scroll through Presets 1-6
• Pressing the SRCE button will toggle between the Factory
XM tuner and Radio as the RSE source. Pressing the power
button or turning the key off will turn off the RSE Controls.
• The factory XM tuner must remain serviced to take
advantage of this feature. Visit www.xmradio.com for a
complete up-to-date channel listing and service options.
• In order for the RSE controls to properly work the XM tuner,
the front XM controls must be set to off.
Using the Factory XM Tuner With the SWC
• To activate the XM controls press and hold the “Source” button until a chime
is heard. The Driver Information Center (DIC) in the instrument cluster will
display “XM Control On” or display XM text.
• Arrow up moves forward through the channels. The channel name and song
name will be displayed on the DIC.
• Arrow down moves backwards through the channels. The channel name will
be displayed on the DIC.
• To store a preset, rst choose the preset location by pressing the “Play”
button repeatedly. The DIC will display the XM preset locations. When the
desired preset location is displayed, tune to the desired station, then press
and hold the “Play” button until a chime is heard. “Preset Saved” will then be displayed on the DIC.
• To recall a preset simply press the “Play” button repeatedly until the desired preset is displayed.
• To de-activate the XM controls press and release the “Source” button. Do not hold the Source button to exit XM control.
PLEASE NOTE: You MUST be installing an aftermarket radio that is equipped with an auxiliary input
to be able to retain the factory XM audio. If the vehicle is equipped with steering wheel controls other
than the ones pictured here, you will not be able to control the factory XM tuner as the
required buttons are not present.
Radio Replacement and Steering Wheel Control Interface
x3
GM3A-RSTX
with OnStar Retention for General Motors Vehicles
Rear Seat Entertainment (RSE); If equipped
1. Vehicles equipped with an overhead screen only:
In this application the GMRVD must be used in order to feed A/V into the factory screen from an aftermarket head unit (head
unit must support A/V out). With the GMRVD, A/V will be passed from the aftermarket head unit to the rear screen and audio
can be heard through the headphones. The GMRVD will also pass the Auxiliary inputs on the rear of the center console to the
aftermarket head unit.
2. Vehicles equipped with an overhead screen AND headrest monitors:
In this application the headrest monitors will function independently from the overhead monitor. Neither video or audio
can be passed to or from the headrest monitors. The overhead monitor will function exactly as described in #1.
OnStar Volume Adjustment for Vehicles w/o SWC
1. If SWC buttons are not present you must use the
programming button on the interface to control the OnStar
audio level during an OnStar connection.
2. When OnStar is active pressing the programming button
will raise the audio level 4 times before returning to the
original level.
Press the programming button
on the side of the interface while
OnStar is active to adjust the
OnStar volume
Technical Support and Product Updates (Firmware)
The GM3A-RSTX can be updated with new rmware as it becomes available using the PAC-UP interface updater (sold separately).
Please visit www.PAC-audio.com/rmware for available updates.
Technical Support
support@PAC-audio.com
866-931-8021