GMC GM3X-HF Instruction Manual

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GM3X-HF
QUICK START INSTALLATION GUIDE FOR GM CLASS II WITH XM TUNER MODULE OR REMOTE CD CHANGER
Created: November 19, 2016
Revised: April 13, 2022

PRODUCT SAFETY & DISCLAIMER
READ ALL INSTRUCTIONS CAREFULLY BEFORE INSTALLING, FAILURE TO DO SO MAY CAUSE
PERSONAL INJURY OR DAMAGE TO PRODUCT AND/OR PROPERTY
This installation guide is provided as a GENERAL installation guide, some vehicles vary and
may require additional steps. We do not accept responsibility for third party labor charges
or modifications. Exercise due-diligence when installing this product.
We do not accept any responsibility for vehicle damage or personal injury resulting from
the installation of this product.
Careless installation and operation can result in equipment damage
Requirements
XM TUNER MODULE (U2K) WITH OR WITHOUT SUBSCRIPTION OR REMOTE
CD CHANGER OR RSE
Introduction
The GM3-HF kit is compatible with virtually all Bluetooth phones, and sounds
great whether using for mobile conversations, streaming music, retaining XM (if
subscribed), remote CD changer or RSE, The GM3-HF works in 2003-12 GM
Class-II vehicles equipped with an XM tuner module, remote CD changer or RSE
(See Fig. 18) If vehicle only has XM and subscription has expired; an AUX input
jack is provided for users to connect and play portable audio devices such as
MP3 players, iPod etc. If subscription is “Active” it remains operational. The
included stylish control button (with built-in microphone) is used to launch Voice
recognition application (Siri, Google Now, Blackberry Assistant etc.). Thanks to
the GM3x-HF kit you keep the stereo, XM, *remote CD changer or DVD while
enjoying Bluetooth features only available on newer cars.
See Frequently Asked question at the end of this guide for more details.
Installation
Radio removal required (Vehicle specific radio removal instructions are not part
of this guide, but may be available upon request)
1. Squeeze blue release tabs on radio 12-pin plug and disconnect (See Fig. 1)
Fig. 1
12-pin plug
2. Connect 12-pin plug (From step 1) to harness 12-pin socket (See Fig. 2)
Fig. 2
3. Connect harness 12-pin plug (See Fig. 3) to radio socket vacated in step 1
Fig. 3
12-pin plug

4. If Vehicle has XM module but subscription has expired:
Connect male-to-male cable audio cable (See Fig. 4) to “AUX”input
jack on module (See Fig. 5)
Fig. 4
Fig. 5
Bluetooth module
5. If vehicle has XM module (subscribed), remote CD changer or RSE:
Connect straight angle 3.5mm plug from harness (See Fig. 6) to
“XM/AUX* input jack on module (See Fig. 5)
Fig. 6
6. Connect installation harness right angle 3.5mm plug (See Fig.6) to jack
on module pigtail (See Fig. 7)
Fig. 7
7. Connect module Red wire to 12V Accessory supply in vehicle. Do not
use 12V constant supply (battery).
Tip: Accessory (ACC) is available on ignition harness (under steering
column). Remove steering column cover and tap into orange or brown wire.
Accessory power may also be available from fuse panel.
Accessory power is active when ignition is in “ACC” or “ON “positions.
8. Connect module black wire to ground (radio chassis is a good option),
cigar lighter plug etc.
Warning: The GM3x-HF will not operate in RAP (Retained Accessory
Power) mode. Ignition must be turned ON in order to hold phone calls,
stream applications or listen to XM (if subscribed)
For module to work in RAP mode we recommend purchasing our TR-4
module
9. The GM3x-HF microphone is built-into the control button. To install;
connect control button 3.5mm plug to “MIC”jack on module (See Fig. 5)

Fig. 8
Control button/Microphone
10. Consider where to install control/microphone button. Keep in mind
control button must be within reach and facing driver for voice
commands and phone dialog (cable is 6ft. long). We recommend
completing the rest of the install prior to securing the
control/mic button to the dash. Once you decide on a location simply
remove tape backing from control /mic button
Ensure no ventilation duct is pointed towards the mic.
It is best to mount button facing driver
USB charging port install options
Should you decide to use charging port, we suggest one of 3 connecting options:
A. Flush to dash/panel requires drilling a ¾” hole in the dash
B. Flush with Support bracket (use this option to mount USB terminal
wherever your installation demands without drilling)
C. Free standing (default)
A. Flush to Dash or Panel (drilling required)
1. Drill a ¾” hole in the dash or panel using a step drill bit or equivalent
(See Fig. 9)
Fig. 9
Step drill bit
2. Insert USB male terminal (See Fig. 10) through ¾” hole created in step
1 and connect to module USB port (See Fig. 11)
Fig. 10
6 ft. USB cable

Fig. 11
Module USB port
3. Push USB head (See Fig. 12) in place and snap to surface (See Fig. 13)
Fig. 12
USB head
Fig. 13
Flush mounted to dash
4. Tuck and secure any extra wire from moving parts and test operation
(See Enabling the AUX section below)
B. USB with Bracket Mount (No drilling)
1. Locate a flat surface at location of choice within 6 ft. of radio to mount
USB support bracket (See Fig. 14) using adhesive backing or screws
Fig. 14
USB mounting bracket
2. Insert USB male terminal through bracket (See Fig. 15) and connect to
module USB port (See Fig. 11)
Fig. 15
3. Push USB head in place and snap to surface (See Fig. 16)
Fig. 16
4. Tuck and secure any extra wire away from moving parts and test
operation ( See Initial Radio Setup )
C. Un-Mounted (Free Standing) Terminal
Connect and install your device USB charging cable.
USB Port is for charging devices requiring less than 1.8A—Power
hungry devices may not charge.

Optional 3.5MM JACK + USB Charing Cable
This option works best for charging and aux input options and can be mounted to
vehicle using included bracket or by drilling hole.
To install simply connect USB and 3.5mm to module USB and AUX input, route
and install terminal to dashboard (drilling required) or bracket (no drilling).
Secure module and proceed to section next section.
Bluetooth pairing and connection
This process is to be performed upon initial install at which the GM3x-HF will
automatically reconnect with paired device upon entering vehicle.
1. Turn vehicle ignition to “ON”.
2. Red LED inside module should flash (otherwise check ground and
accessory wires)
3. Access smartphone Bluetooth menu settings, and search (scan) for
devices.
4. Select BlitzBlueG2 and click “Connect”
Note: Supports multiple phones but connects to only one phone at a time.
Warning: Caller ID or text display from music apps is not possible.
Operating Bluetooth device by pressing the control button or Voice
recognition application. Use factory radio volume button to control
playback level

Bluetooth operation
1. Press “BAND” button on radio to enter XM mode or CD/AUX button to
enter external CD changer or DVD mode
2. Use radio volume button to set playback level
Music Commands
Use control button to perform the following music commands:
To
Proceed this way
Pause a Song
Press and release button
Resume Play
Press and release button
Skip to next song
Press button twice
Skip to Previous Song
Press button 3 times
AUX option* (XM/Aux/DVD/changer)
Press button 4 times
Activate Voice Control
Press/hold button for 2 seconds
Switch out of XM Mode
Press and release button
Phone Commands
Use control button to perform the following phone commands:
To
Proceed this way
Answer call
Press and release button
End call
Press and release button
Reject incoming call
Press button twice (call goes to VM)
Cancel outgoing call
Press button twice
Activate Voice Control
Press/hold button for 2 seconds
Notes:
1. If playback is distorted, adjust volume on Bluetooth device.
2. To reset Module press and Hold button for 5 seconds (this will not
un-pair phone or erase stored phones)
3. On incoming calls, ring tone will play on car speakers
4. Bluetooth range is approximately 30 ft. Ensure device is within range
5. Voice command compatible with Apple (Siri), Android (Google Now),
Blackberry (Assistant)
6. * Control button will not control XM/Aux/CD changer/DVD functions.
Use radio button assigned to these functions or aux device built-in
control for music selection.
7. Upon ending call, music streaming resumes, however to resume
XM/AUX playback, press control button 4 times.
If successful go ahead and Reinstall the Radio
Congratulations, you’ve just updated your vehicle to support new technology
while preserving the original radio and dash components.
Enjoy!

Frequently asked questions and troubleshooting
1. My vehicle has XM module but subscription has expired. Will the GM3x-
HF work?
YES.If subscription has expired, the module XM/AUX input can be used to
connect and play an audio device (Mp3 Players, iPod, DVD, iPad etc.)Aux.
input option is not available to active subscribers or vehicles with remote
CD changer or RSE.
2. I’m not the original owner and don’t know if vehicle has XM module.
How can I find out without ripping it apart?
Turn radio “ON”, press “BAND” button repeatedly to cycle through
AM/FM/CD/XM1/XM2. If only AM/FM is displayed, vehicle does not have
required XM module.
3. Does the GM3x-HF work on all GM radios?
Works on Navigation and non-Navigation GM Class-II radios with XM module
with or without subscription or remote/external CD changer. (Changer
built-into radio is not external/remote) or RSE.
4. Can I control Smartphone music from radio buttons?
NO; you must continue to use audio device built-in controls or included
control button and/or voice commands to operate audio device.
Volume button on radio can be used to set playback level.
5. What do I need for the GM3x-HF to work in my vehicle?
For the GM3x-Hf to work, your vehicle must have at least one of the
following factory options: XM module (With or without subscription),
external/remote CD changer or RSE (rear seat entertainment-DVD)
6. How do I listen to factory option (XM, or remote CD changer or RSE)?
Press BAND, XM or CD/AUX button on radio to enter XM or CD changer or
RSE mode (if not already) then press control button 4 times. These
instructions also apply to enable Aux playback option (instead of
XM/CD changer)
7. Where is the best place to install control button/mic?
We found that having the control button/mic mounted higher on the dash
worked best, but users can experiment with different location and decide
which works best for them.
8. Will the stereo mute when I receive or make a phone call?
This system will mute if radio is in “XM”, “CD changer” or “RSE”mode
(Bluetooth mode). If in AM/FM mode, radio will not mute and you must also
switch to Bluetooth Mode (XM, RSE or External changer)
9. How do I pair a second phone to module?
In order to pair a second phone make sure no other phones are connected.
Once Bluetooth is disabled on first device, module will be ready for pairing.
10. Will I be able to use module USB port to connect and play music from
flash drives?
No. The USB port is for charging only.
11. My radio has a built-in 6-CD changer. Will the GM3x-HF work?
As the name would imply, external or remote CD changer refers to changer
mounted in remote location (e.g. armrest, glove box, trunk, hatch, under
seat etc.)
The built-in changer to factory radio (6-CD changer radio) is internal
and not the external changer referenced herein. Remote or external
CD changers are installed in glove box, armrest, trunk, hatch etc. and
required for module to work as described.
Disclaimer
• This product has no affiliation with GM
• We’re not liable for misuse of this product.
•We recommend professional installation
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