LG SNC4R User manual

SERVICE MANUAL
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS”
IN THIS MANUAL.
MODEL: SNC4R (SNC4R, SPH4B-W) / SPJ4-S (SPJ4-S, S65S3-S)
P/NO : AFN30054142 MARCH, 2021
MODEL: SNC4R (SNC4R, SPH4B-W)
SPJ4-S (SPJ4-S, S65S3-S)
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Wireless Sound Bar
“Any reproduction, duplication, distribution (including by way of email, facsimile or other
electronic means), publication, modification, copying or transmission of this Service Manual is
STRICTLY PROHIBITED unless you have obtained the prior written consent of the LG Electronics
entity from which you received this Service Manual. The material covered by this prohibition includes,
without limitation, any text, graphics or logos in this Service Manual.”

1-1
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
CONTENTS
SECTION 1 ........ GENERAL
SECTION 2 ........ CABINET & MAIN CHASSIS
SECTION 3 ........ ELECTRICAL
SECTION 4 ........ WIRELESS SUBWOOFER PART
SECTION 5 ........ WIRELESS RECEIVER PART

1-2
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
SECTION 1
GENERAL
CONTENTS
ESD PRECAUTIONS......................................................................................................................................... 1-3
LOCATION OF CUSTOMER CONTROLS........................................................................................................ 1-4
WIRELESS SUBWOOFER CONNECTION....................................................................................................... 1-5
REAR SPEAKERS CONNECTION ................................................................................................................... 1-6
HIDDEN KEY MODE ......................................................................................................................................... 1-7
FIRMWARE UPDATE GUIDE ........................................................................................................................... 1-8
SPECIFICATIONS ........................................................................................................................................... 1-11

1-3
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
ESD PRECAUTIONS
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components
commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated
circuits and some field-effect transistors and semiconductor chip components. The following techniques should
be used to help reduce the incidence of component damage caused by static electricity.
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off
any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a
commercially available discharging wrist strap device, which should be removed for potential shock reasons
prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ESD devices, place the assembly on a conductive surface
such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ESD devices.
4. Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static" can
generate electrical charges sufficient to damage ESD devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD
devices.
6. Do not remove a replacement ESD device from its protective package until immediately before you are
ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by
conductive foam, aluminum foil or comparable conductive materials).
7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the
protective material to the chassis or circuit assembly into which the device will by installed.
CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER
SAFETY PRECAUTIONS.
8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion
such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate
static electricity sufficient to damage an ESD device).
CAUTION. GRAPHIC SYMBOLS
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS
INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED
“DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF
ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE
SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE
LITERATURE.

1-4
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
LOCATION OF CUSTOMER CONTROLS
Front panel
Rear panel
Display Window
- Display window will be darkened automatically if there is no key input for 15 seconds.
When you press any button, the display window will brighten.
Remote sensor
(Standby)
- Switches the unit ON or OFF.
F(Function)
- Select the function and input source by pressing Frepeatedly.
Input source / Function Display
Optical LG Sound Sync (Wired) OPT
Bluetooth BT
LG Sound Sync (Wireless) LG TV
USB USB
+/−(Volume)
- Adjusts volume level.
DC IN
- Connect to the AC adapter.
OPTICAL IN
- Connect the OPTICAL IN jack on the back of the unit to OPTICAL OUT jack on the TV.
USB Port
- Connect USB memory device to the USB port on the back of the unit.
1
2
3
1
2
3

1-5
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
WIRELESS SUBWOOFER CONNECTION
LED indicator of wireless subwoofer
LED Color Status
Yellow - green
(Blink)
The connection is trying.
Yellow - green The connection is completed.
Red
The wireless subwoofer
is in standby mode
or the connection is failed.
Off
(No display)
The power cord of wireless
subwoofer is disconnected.
Setting up the wireless subwoofer
for the first time
1. Connect the power cord to the subwoofer and plug
the power cord into a power outlet.
2. Turn on the main unit : The sound bar and wireless
subwoofer will be automatically connected.
- Yellow - green on the rear of wireless subwoofer
turns on.
Manually pairing wireless subwoofer
When your connection is not completed, you can
check red LED on the wireless subwoofer and the
wireless subwoofer does not make sound. To solve
the problem, follow the steps below.
1. Press PAIRING button on the rear of the wireless
subwoofer.
- The yellow - green LED on the rear of the wireless
subwoofer blinks quickly. (If the green LED does
not blink, press and hold the PAIRING.)
2. Turn on the sound bar.
- Pairing is completed. The yellow - green LED on
the front of the wireless subwoofer turns on.
Note :
•It takes a few seconds (and may take longer) for the
main unit and the subwoofer to communicate with
each other and make sounds.
•The closer the main unit and the subwoofer, the
better sound quality. It is recommended to install the
main unit and the subwoofer as close as possible
and avoid the cases below.
- There is a obstacle between the main unit and the
subwoofer.
- There is a device using same frequency with this
wireless connection such as a medical equipment,
a microwave or a wireless LAN device.
- Keep the sound bar and the subwoofer away from
the device (ex. wireless router, microwave oven,
etc.) over 1m to prevent wireless interference.
XG

1-6
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Connecting the rear speakers
1. Connect the black stripe wire to the terminal
marked - (minus) and the other end to the terminal
marked + (plus).
2. Connect the wireless receiver and the rear
speakers (right, left) with the speaker cables.
Color Position
Grey Rear right
Blue Rear left
Note :
You need to purchase the wireless rear speakers kit
(SPK8-S) to enjoy surround sound.
Caution :
•Use the speaker supplied with this unit only. Using
any other speaker may cause malfunction.
•Be sure to match the speaker cable to the
appropriate terminal on the components: + to + and
– to –. If the cables are reversed, the sound will be
distorted and will lack bass.
LED indicator of wireless receiver
LED Color Status
Yellow - green
(Blink) The connection is trying.
Yellow - green
The wireless receiver is receiving
the signal from the sound bar.
Red The wreless receiver is in
standby mode.
Off
(No display)
The power cord of wireless
receiver is disconnected
Setting up the wireless receiver for the
first time
1. Connect the power cord to the wireless receiver
to the outlet.
2. Turn on the main unit : The sound bar and
wireless receiver will be automatically connected.
- Yellow - green LED on the wireless receiver
turns on.
Manually pairing wireless receiver
When your connection is not completed, you can
see the red LED on the wireless receiver and rear
speakers are not made sound. To solve the problem,
follow the below steps.
1. Press PAIRING button on the rear of the wireless
receiver.
- The yellow - green LED on the wireless receiver
blinks quickly.
2. Turn on the main unit
- Paring is completed. The yellow - green LED on
the wireless receiver turns on.
REAR SPEAKERS CONNECTION

1-7
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
HIDDEN MODE KEYS
EEPROM EDIT Main unit ‘ (Volume)’ + Remote control ‘NIGHT ON’
EEPROM CLEAR (Initialize) Main unit ‘ (Volume)’ + Remote control ‘'ASC ’
VERSION CHECK Main unit ‘ (Volume)’ + Remote control ‘ (Play/Pause)’
HIDDEN KEY MODE

1-8
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
1. Preparation
1) SL4Y Series Units : Main Unit, Wireless Subwoofer Unit, Rear Speaker Unit(optional).
2) SL4Y RCU.
3) USB Memory.
4) Android Device with “Music Flow Bluetooth” App for FOTA update, “Version Check APP” for Version Check.
※Take care not to power off during update.
※Do format USB memory before update (FAT32 file system).
FIRMWARE UPDATE GUIDE
<Main Unit>
Necessary
<Wireless Subwoofer Unit>
If wireless subwoofer rx module
of primary unit is updated.
<USB Memory>
for USB update
<Rear Speaker Unit>
Optional as model suffix
If wireless rear rx module is updated
<RCU>
Necessary

1-9
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
2. USB Update
Step 1. Prepare SL4 update binaries.
Update module Prefix & Extension Filename Sample
DSP DSP_SL4Y*.ROM DSP_SL4_1812100_PRO1_rev1619.rom
Wireless Subwoofer Tx WOOFERTX_SL4Y*.BIN WOOFERTX_SL4_190007_181206_checksum_C7CA.bin
Wireless Subwoofer Rx WOOFERRX_SL4Y*.BIN WOOFERRX_SL4_191008_181206_checksum_90BE.bin
Wireless Rear Tx REARTX_SL4Y*.BIN REARTX_SL4_BAR_19.40.06_CHECKSUM_BEA0.bin
Wireless Rear Rx REARRX_SL4Y*.BIN REARRX_SL4_Ver185001_171128_checksum_DFDF.bin
PEQ PEQ_SL4Y*.BIN PEQ_SL4_1812070_PRO1_0EAD.bin
Option OPT*.BIN OPTION_SL4Y_EUS.bin
*
SLx : “SL4”, depends on model option.
Step 2. Copy all updated SL5/ SL6 binaries to USB memory.
Step 3. Power on SL5/ SL6 main unit.
Step 4. If there is an updated wireless subwoofer rx binary in update list,
you need to pair between main unit and subwoofer unit before start update.
Step 5. If there is an updated wireless rear rx binary in update list,
you need to pair between main unit and rear speaker unit before start update.
Step 6. Press Function key to change function to USB.
Verify whether USB function is or not by VFD.
Step 7.Attach USB which has update binaries to the USB slot back of SL4Y main unit.
Step 8. Update will start automatically.
VFD Model : Check VFD what module is in progress one by one.
USB
Update module VFD display
DSP
Option
PEQ
Wireless Subwoofer Rx
Wireless Subwoofer Tx
Wireless Rear Tx
Wireless Rear Rx
D-UP
OP-UP
EQ-UP
WR 00
WT 00
RT 00
RR 00
<SL4Y Series VFD Display in Update>
※The numbers in VFD display of wireless modules will
increase in progress as progress percent from 00 to 100.

1-10
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
USB Update
Step 9. SL4Y main unit will be off automatically after update finish.
Step 10. Power on SL4Y main unit again.
Step 11. Check the current versions to verify whether the update was successfully completed or not.
1) Press “Version Check” hidden key
• Version Check Hidden Key : Press Set “Vol-” + RCU “Play/Pause” for 3secs.
2) SL4Y shows the version of all modules in the order shown below.
• The order that SL4Y shows version in version check hidden mode.
DSP Wireless Subwoofer Tx Wireless Subwoofer Rx Wireless Rear Tx
Wireless Rear Rx PEQ Option
3) Compare the version VFD shows and you updated.
+
Module VFD display sample
DSP
Wireless Subwoofer Tx
Wireless Subwoofer Rx
Wireless Rear Tx
Wireless Rear Rx
PEQ
Option
* Press Play/pause button to see
next option value.
E1812100
WT190007
WR191008
RT194006
RR185001
Q1812070
OP00-00
<SL4 VFD Display in Version Display>

1-11
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
SPECIFICATIONS
• GENERAL
Power consumption Refer to the main label.
Networked standby : 0.5 W
(If all network ports are activated.)
AC adapter Model : DA-38A25
Manufacturer : Asian Power Devices Inc.
Input : 100 - 240 V ~ 50 - 60 Hz
Output : 25 V 1.52 A
Dimensions (W x H x D) Approx. 890.0 mm x 57.0 mm x 85.0 mm With foot
Operating temperature 5 °C to 35 °C
Operating humidity 5 % to 90 %
Bus Power Supply (USB) 5 V 500 mA
Available Digital Input Audio
Sampling Frequency 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz
Available Digital Input Audio format Dolby Audio, DTS Digital Surround, PCM
• INPUT/OUTPUT
OPTICAL IN 3 V (p-p), Optical jack x 1
• AMPLIFIER (RMS Output)
Total 300 W RMS
Front 50 W RMS x 2 (4 Ωat 1 kHz, THD 10 %)
Subwoofer 200 W RMS (3 Ωat 80 Hz, THD 10 %)
• WIRELESS SUBWOOFER
Power requirements Refer to the main label on the wireless subwoofer.
Power consumption Refer to the main label on the wireless subwoofer.
Type 1 Way 1 Speaker
Impedance 3 Ω
Rated Input Power 200 W
Max. Input Power 400 W
Dimensions (W x H x D) Approx. 171.0 mm x 390.0 mm x 261.0 mm
SPJ4-S (SPJ4-S, S65S3-S)
• WIRELESS RECEIVER
Power requirements Refer to the main label on the wireless receiver.
Power consumption Refer to the main label on the wireless receiver.
Rear 70 W RMS x 2 (3 Ωat 1 kHz, THD 10%)
Dimensions (W x H x D) Approx. 60.0 mm x 220.0 mm x 175.0 mm
(2.4 inch x 8.7 inch x 6.9 inch)
• REAR SPEAKERS (EACH)
Type 1 Way 1 Speaker
Impedance 3 Ω
Rated Input Power 70 W RMS
Max. Input Power 140 W RMS
Dimensions (W x H x D) Approx. 100.0 mm x 140.0 mm x 100.0 mm
(3.9 inch x 5.5 inch x 3.9 inch)
• Designs and specifications are subject to change without prior notice.

1-12
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.

2-1
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
SECTION 2
CABINET & MAIN CHASSIS
CONTENTS
DISASSEMBLY INSTRUCTIONS ..................................................................................................................... 2-2
1. HOW TO DISASSEMBLE THE MAIN SET .............................................................................................. 2-2
EXPLODED VIEWS ........................................................................................................................................... 2-7
1. MAIN UNIT SECTION............................................................................................................................... 2-7
2. WIRELESS SUBWOOFER SECTION.................................................................................................... 2-11
3. WIRELESS RECEIVER SECTION ......................................................................................................... 2-15
4. REAR SPEAKER SECTION ................................................................................................................... 2-17
5. PACKING ACCESSORY SECTION ....................................................................................................... 2-19

2-2
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
DISASSEMBLY INSTRUCTIONS
Figure 1-2
Figure 1-1
1. HOW TO DISASSEMBLE THE MAIN SET
2) Remove the Case Bottom Assembly.
1) Remove the 19 screws.

2-3
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 1-4
Figure 1-3
HOW TO DISASSEMBLE THE MAIN SET
4) Remove the SPK Chamber L/R Assembly.

3) Remove the 2 screws, Disconnect the Harmess/FFC cables (KEY, SPK) and Remove the Main PCB Assembly.
 

2-4
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 1-6
Figure 1-5
HOW TO DISASSEMBLE THE MAIN SET
6) Remove the 4 screws and Disconnect FFC cables (BT, Wireless).
5) Remove the L/R Deco Assembly.


BT
Wireless

2-5
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 1-8
Figure 1-7
HOW TO DISASSEMBLE THE MAIN SET
8) Remove the EMI Shield Tape of Bottom side.
7) Remove the EMI Shield Tape.


2-6
Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
Figure 1-9
HOW TO DISASSEMBLE THE MAIN SET
9) Disassembly finish.

Copyright © 2021 LG Electronics Inc. All rights reserved.
Only for training and service purposes.
F
HCABLE1
C
D
B/T
A52
CABLE2
MAIN
F
J
J
D
C
A
B
B
A46
266
WIRELESS
A54
CABLE3
A80L
A80R
A42
262
264
A41
H
253
A55
A
CABLE4
WIRELESS
A54
265
E
EXPLODED VIEWS
1. MAIN UNIT SECTION
2-7 2-8