LG SN4A Service Manual Download Page 3

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1-2

Only for training and service purposes.

SECTION 1

SUMMARY

CONTENTS

PRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO PRODUCTS

.................................................... 1-3

SERVICING PRECAUTIONS

............................................................................................................................ 1-4

• GENERAL SERVICING PRECAUTIONS
• INSULATION CHECKING PRODEDURE
• ELECTROSTATICALLY SENSITIVE (ES) DEVICES

LOCATION OF CUSTOMER CONTROLS

........................................................................................................ 1-5

WIRELESS SUBWOOFER CONNECTION

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HIDDEN KEY MODE

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SOFTWARE UPDATE GUIDE

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SPECIFICATIONS

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Summary of Contents for SN4A

Page 1: ...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...

Page 2: ...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 ...

Page 3: ...NTS PRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO PRODUCTS 1 3 SERVICING PRECAUTIONS 1 4 GENERAL SERVICING PRECAUTIONS INSULATION CHECKING PRODEDURE ELECTROSTATICALLY SENSITIVE ES DEVICES LOCATION OF CUSTOMER CONTROLS 1 5 WIRELESS SUBWOOFER CONNECTION 1 6 HIDDEN KEY MODE 1 7 SOFTWARE UPDATE GUIDE 1 8 SPECIFICATIONS 1 15 ...

Page 4: ...ign Be sure that the safety purpose of the polarized line plug has not been defeated 3 Soldering must be inspected to discover possible cold solder joints solder splashes or sharp solder points Be certain to remove all loose foreign particles 4 Check for physical evidence of damage or deterioration to parts and components for frayed leads or damaged insulation including the AC cord and replace if ...

Page 5: ... more than 1Mohm Note 1 Accessible Conductive Parts include Metal panels Input terminals Earphone jacks etc Electrostatically Sensitive ES Devices Some semiconductor solid state devices can be damaged easily by static electricity Such components commonly are called Electrostatically Sensitive ES Devices Examples of typical ES devices are integrated circuits and some field effect transistors and se...

Page 6: ...ource Function Display Optical ARC LG Sound Sync Wired OPT HDMI ARC Bluetooth BT LG Sound Sync Wireless LG TV HDMI IN HDMI 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 HDMI IN Connect HDMI IN jack on the back of the unit to HDMI OUT jack on the external device You can enjoy the sound...

Page 7: ...reless 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 tak...

Page 8: ... rights reserved Only for training and service purposes HIDDEN KEY MODE HIDDEN MODE KEYS EEPROM OPTION EDIT Main unit VOL Remote Control EEPROM CLEAR Initialize Main unit VOL Remote Control VERSION CHECK Main unit VOL Remote Control Play Pause ...

Page 9: ... FOTA update Version Check APP for Version Check Caution Take care not to power off during update Do format USB memory before update FAT32 file system SOFTWARE UPDATE GUIDE Main Unit Necessary RCU Necessary Wireless Subwoofer Unit If wireless subwoofer rx module of primary unit is updated USB Memory for USB update Android Device Music Flow Bluetooth must be installed for FOTA update Version Check ...

Page 10: ...re 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 whic...

Page 11: ...k Hidden Key Press Set Vol RCU Play Pause for 3secs 2 SN4 shows the version of all modules in the order shown below The order that SN4 shows version in version check hidden mode MICOM PEQ B E MEQ Wireless Subwoofer Tx Wireless Subwoofer Rx Boot loader do not mind Option 3 Compare the version VFD shows and you updated Module VFD display sample MICOM PEQ B E MEQ Wireless Subwoofer Tx Wireless Subwoo...

Page 12: ...4 main unit and Android Device with Music Flow Bluetooth FOTA Update only sup ports B E Main and MICOM module update Step 2 Power on SN4 main unit Step 3 Execute Music Flow Bluetooth App Step 4 Connect between android device and SN4 main unit by Music Flow Bluetooth App 3 Using APP FOTA Firmware update Over The Air ...

Page 13: ...ep 5 Check the SN4 current version with Music Flow Bluetooth App Step 6 If the main and micom version and of SN4 is already the latest version Current version and Latest version in pop up window Device version info are same Also update icon must be disabled Using APP FOTA Firmware update Over The Air ...

Page 14: ...fo are different Also update icon must be enabled touch update icon to start FOTA update Step 8 FOTA update will be progress automatically as below sequence 1 Download binary from server 2 Transfer binary from Android device to SN4 main unit 3 SN4 main unit executes update 1 Download binary 2 Transfer to SN4 3 Update progress Music Flow Bluetooth App VFD Model Current Function Using APP FOTA Firmw...

Page 15: ... service purposes Step 9 SN4 main unit will be off automatically after update finish Step 10 Power on SN4 main unit again Step 11 Check the current versions to verify whether the update was successfully completed in such a way of Step 5 6 Using APP FOTA Firmware update Over The Air ...

Page 16: ... kHz 44 1 kHz 48 kHz 88 2 kHz 96 kHz Available Digital Audio In format Dolby Audio DTS Digital Surround PCM INPUT OUTPUT OPTICAL IN 3 V p p Optical jack x 1 HDMI IN 19 Pin Type A HDMI connector x 1 HDMI OUT 19 Pin Type A HDMI connector x 1 AMPLIFIER RMS Output Total 400 W RMS Front 90 W RMS x 2 4 Ω at 1 kHz THD 10 Subwoofer 220 W RMS 3 Ω at 80 Hz THD 10 WIRELESS SUBWOOFER Power requirements Refer ...

Page 18: ...d Only for training and service purposes SECTION 2 CABINET MAIN CHASSIS CONTENTS DISASSEMBLY INSTRUCTIONS 2 2 1 HOW TO DISASSEMBLE THE MAIN UNIT 2 2 EXPLODED VIEWS 2 7 1 MAIN UNIT SECTION 2 7 2 WIRELESS SUBWOOFER SECTION 2 11 3 PACKING ACCESSORY SECTION 2 15 ...

Page 19: ...21 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 ...

Page 20: ...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 ...

Page 21: ...tronics 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 ...

Page 22: ...ht 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 ...

Page 24: ...ics Inc All rights reserved Only for training and service purposes F H CABLE1 C D B T A51 CABLE2 MAIN F G G D E C A B B A46 WIRELESS A54 CABLE3 A80L A A80R A42 262 264 A41 H 253 A55 266 2 8 2 7 EXPLODED VIEWS 1 MAIN UNIT SECTION ...

Page 25: ...179301 Module RF Full Module RxTx WL1SB21_ETWADYEC02_1 2_IA9QH5 A55 EBR88178301 PCB Assembly SL4 SL5 Key TOTAL ASSY A80L ABQ76481726 Case Assembly SN4 Case Assy L Chamber A80R ABQ76481727 Case Assembly SN4 Case Assy R Chamber INDIVIDUAL PARTS 253 ABH76819601 Button Assembly SL5 Button Assy 262 MCQ62096460 Damper CUTTING THERMOPLASTIC HOME THE 264 AEJ74999618 Holder Assembly HOME THEATER SL5YF ABS ...

Page 26: ...2 2 11 954 955 D E WIRELESS SMPS A B F G F 958 A900 951 C D AMP B G E C A47W CN901 A54W 959 A45W 2 WIRELESS SUBWOOFER SECTION NOTES THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE ...

Page 27: ...nt Kind Array PCB Assem SN4 Woofer AMP SPL4M W Total A47W EBR32310001 PCB Assembly Power SPN4B W USA Total Assy only No A54W EAT65179301 Module RF Full Module RxTx WL1SB21_ETWADYEC02_1 2_IA9QH5 951 MGC63804110 Panel Rear MOLD ABS SPK S55A1 D MOLD Rear 954 MCZ63611901 Duct CUTTING PAPER SPK S55A1 D OTHE 955 MCZ63631801 Duct MOLD HIPS SPK S45A1 D MOLD INN 958 EAD62131520 Cable FFC 26P005D H2 1FS N 9...

Page 28: ...y for training and service purposes 833 AC adapter 900 Remote control 300 Power cord Main unit Power cord Woofer 300W 806 Optical cable 3 PACKING ACCESSORY SECTION 835 Wall bracket 836 Screws 2 NOTES IF YOU WANT TO SVC A PACKAGE BAG w BOX PLEASE REQUEST AT A TIME ...

Page 29: ...1210 Cable Assembly OPTICAL 1P OPTICAL OPTICAL 150 OR 806 EAD63727901 Cable Assembly 210 26424 OPTICAL OPTICAL 1 5M OR 806 EAD63345601 Cable Assembly POF1 BB2B 1500 02 OPTICAL OPTI w 833 EAY64290801 Adapters DA 38A25 AAAA 100 240V 25V 1 5 900 AKB75595361 Remote Controller Assembly MA6 SN SL10 9 8 7 6 5 4 Add OR 900 AKB75595331 Remote Controller Assembly MA6 SM SL10 9 8 7 6 5 4 Soundb 835 AAA774270...

Page 30: ...NIT ON NO MESSAGE OR HELLO ON FRONT PANEL 3 5 2 NO SOUND 3 9 3 PROTECTION ERROR 3 13 ELECTRICAL TROUBLESHOOTING GUIDE 3 15 1 ADAPTER POWER CIRCUIT 3 15 2 KEY PART 3 24 3 USB FUNCTION 3 25 4 OPTICAL FUNCTION 3 26 WAVEFORMS OF MAJOR CHECK POINT 3 27 1 CRYSTAL 3 27 2 FLASH MEMORY 3 27 3 TACT KEY 3 28 4 USB 3 29 5 REMOTE CONTROL 3 30 6 OPTICAL 3 31 7 FM 3 32 CIRCUIT VOLTAGE CHART 3 33 PRINTED CIRCUIT ...

Page 31: ...N CN108 CN104 LCD WIRELESS MODULE REAR BOX WIRELESS MODULE WOOFER BT MODULE OPTICAL TUNER 26 PIN FFC CABLE 26 PIN FFC CABLE 12 PIN FFC CABLE 2 PIN HARNESS REMOCONE CN101 JK300 DC JACK CN704 CN703 CN103 FR FL MAIN PCB EAX68366602 1 2T FR4 4LAYER KEY PCB EAX68503501 1 2T FR4 2LAYER CN102 14 PIN FFC CABLE WIRING DIAGRAM ...

Page 32: ... SPDIF DC_DC LDO Switch IC FL_P N TWL_P N DDR3 128MB A RA 0 14 27MHz Serial Flash 16MB MCLK LRCK BCK ADC_DAT WL_MUTE INIT RST MSG_RDY CLK DAT PWM_BCK LRCK DATA2 Wireless Woofer Wireless Module RX LCD_DO CLK BL_CTRL S Flash 1MB POWER FUNC VOL SPI MTK MT8502 FL LPF L AMP IC TAS5612L A FR LPF L AMP IC TAS5612L A MICOM MSP430F5438AIPZR 100pin 2 PWM PS9860 Wireless Module TX 5G HDMI OUT HDMI IN OPTICAL...

Page 33: ...P430F5326 1 2V 1 2V D_3 3V 80mA 12V 3 3VA WL_WF_CTRL 1000mA D33_CTRL DCDC SY8089A Switch SY6288C3 DDR3 ADC PCM1808 DCDC_12_15_CTRL 90mA 60mA VCC_5V 12VA 3 3VA RCU OPTICAL 10mA 10mA 3 3VA WIRELESS Woofer 5G 25mA 3 3VA Switch SY6288C3 HDMI_5 1V PWR_CTRL RBOX_3V3 65mA LDO or Switch DCDC Control VCC CTRL Signal 100mA 20mA WIRELESS Rear 5G Switch SY6288C3 WL_RBOX_CTRL HDMI 18 mA Switch SY6288C3 PWR_GD ...

Page 34: ...asure 1 Please check 25 VA of IC302 pin2 VIN 2 If 25 VA is abnormal please check adapter 3 If 25 VA is OK but 12 VA is abnormal pin3 of IC302 VOUT replace MAIN board 1 1 3 Service hint Any picture Remark MAIN board top view C306 100nF C300 10uF 35V C307 100nF C320 10uF 35V C313 10uF 35V C323 10uF 35V NC C302 100nF C312 10uF 35V C351 33pF R301 47K 1 R306 22 R328 100K R305 3 3K 1 R335 100K R300 51K ...

Page 35: ...o troubleshoot Countermeasure 1 Please check 5 1 VA of IC305 pin2 2 If 5 1 VA is abnormal replace MAIN board 1 2 3 Service hint Any picture Remark MAIN board bottom view C314 100nF 1 C310 10uF 35V 3 C316 10uF 16V C308 10uF 35V 3 NC C319 10pF C321 10uF 16V C303 1uF 1 C318 10uF 16V R355 33 R303 100K R310 13K 1 R327 8 2K 1 R312 62K 1 12VA 5 1VA DGND DGND DGND DGND DGND D301 1 C 2 A 3 C C3A3 100nF R37...

Page 36: ...leshoot Countermeasure 1 Please check 3 3 VA of IC301 pin3 2 If 3 3 VA is abnormal replace MAIN board 3 If 5 1 VA is OK replace MAIN board 1 3 3 Service hint Any picture Remark MAIN board top view C322 10uF 10V C354 10uF 10V C309 10uF 16V C328 47pF R356 4 7K R309 24K 1 R357 100K 1 FB305 5 1VA 3 3VA DGND DGND DGND C3A4 100nF IC301 1 EN 2 GND 3 LX 4 VIN 5 FB R373 0OHMNC R304 240K 1 C3A5 100nF C3A8 1...

Page 37: ...ease check CN101 VCC_5V of CN101 pin1 2 If VCC_5 V is abnormal replace MAIN board 3 If VCC_5 V OK replace LCD module 1 4 3 Service hint Any picture Remark MAIN board top view DGND DGND LCD_DAT DGND LCD_BL LCD_STB LCD_CLK LCD_RST LCD_CD C128 10nF C157 10uF 10V M C120 100nF VCC_5V R191 220 M R192 220 M FB105 F_5V LCD_BL LCD_STB LCD_CD LCD_CLK LCD_DAT LCD_3V3 LCD_GND VB0 VB1 VB0 VLCD Q104 E C B 3 3VA...

Page 38: ...T_WAKEUP BT_STBY pin7 6 3 2 1 If no signal please replace MAIN board 2 1 3 Service hint Any picture Remark MAIN board top view C124 10uF C125 100nF 7 2 1 C F p 2 2 NC FL101 NC 1 2 3 4 C130 100nF CN102 1 3 3VA 2 3 3VA 3 NC 4 GND 5 GND 6 USB_DP 7 USB_DN 8 GND 9 GND 10 RESET 11 BT_WAKEUP 12 MCU_STBY ZD103 Z02W3 9V 1 2 3 FB104 PZ1608U221 1R4TF USB0_DN_BT 3 3VA USB0_DP_BT 6 2 1 C F n 0 0 1 DGND TB01 TB...

Page 39: ...hoot Countermeasure 1 Please check 3 3 VA at R209 2 If 3 3 VA is ok please check OPT_IN signal C208 when OPTICAL mode 3 If signal is abnormal replace MAIN board 2 2 3 Service hint Any picture Remark MAIN board top view OPTICAL JACK 96KHz 3 3VA JK202 1 OUT 2 GND 3 VCC R209 82 R202 100 C208 15pF R201 560 DGND DGND OPT_IN OPT_DET C207 1uF C224 100pF MPEG MICOM OPTICAL R209 R209 C208 C208 JK202 JK202 ...

Page 40: ...easure 1 Please check soldering status of HDMI jack and check HDMI_5V at IC308 pin1 2 If soldering status and 5 1 VA are abnormal replace MAIN board 2 3 3 Service hint Any picture Remark MAIN board top view C360 1nF C361 10uF C363 1uF C362 10uF C359 1uF C358 10uF C399 100nF 1 NC HDMI_CTRL R369 NC R383 4 7K 5 1VA HDMI_5 1VA DGND DGND DGND IC308 1 OUT 2 GND 3 OCB 4 EN ENB 5 IN 5 1VA to HDMI_5 1VA IC...

Page 41: ... 0 1 C200 220uF NC DGND 1 0 2 C F n 0 0 1 USB1_DP USB1_DN FB201 1 2 3 4 D201 uCLAMP0561P R210 4 7 R211 4 7 USB MPEG ONE POINT REPAIR GUIDE NO SOUND 2 4 USB 2 4 1 Solution Replace MAIN board 2 4 2 How to troubleshoot Countermeasure 1 Please check USB_5V at JK201 pin1 2 If soldering status and voltage has abnormal status replace MAIN board 2 4 3 Service hint Any picture Remark MAIN board bottom view...

Page 42: ...lace MAIN board 3 1 2 How to troubleshoot Countermeasure 1 Check DC Voltage of speaker out FL TWL CN703 pin1 2 3 4 FR TWR CN704 pin1 2 4 5 2 Check resistor crack cold solder of PWM IC out AR601 AR602 3 If PWM IC out is ok and speaker out FL FR TWL TWR has DC voltage replace MAIN board 3 1 3 Service hint Any picture Remark MAIN board top view IC600 IC600 CN703 CN703 CN704 CN704 AR601 AR601 AR602 AR...

Page 43: ...N ERROR No display or No Sound 3 2 B BURNT PROTECTION 3 2 1 Solution Replace MAIN board 3 2 2 How to troubleshoot Countermeasure 1 Check voltage 12 V of IC700 IC701 at pin1 2 if 12 V has problem refer to STEP 1 1 2 If 12 V is OK replace MAIN board 3 2 3 Service hint Any picture Remark MAIN board bottom view IC701 IC701 IC700 IC700 ...

Page 44: ...nd service purposes ELECTRICAL TROUBLESHOOTING GUIDE No 3 3 VA Check F301 Voltage 25 VA Check FB305 Voltage 5 1 VA Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check R373 Voltage 3 3 VA Replace IC302 Replace IC301 YES YES NO NO OK 1 ADAPTER POWER CIRCUIT ...

Page 45: ... and service purposes ELECTRICAL TROUBLESHOOTING GUIDE ADAPTER POWER CIRCUIT No 1 5 V Check F301 Voltage 25 VA Check FB305 Voltage 5 1 VA Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check R374 Voltage 1 5 V Replace IC302 Replace IC303 YES YES NO NO OK ...

Page 46: ... and service purposes ELECTRICAL TROUBLESHOOTING GUIDE ADAPTER POWER CIRCUIT No 1 2 V Check F301 Voltage 25 VA Check FB305 Voltage 5 1 VA Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check R376 Voltage 1 2 V Replace IC302 Replace IC311 YES YES NO NO OK ...

Page 47: ...ning and service purposes ELECTRICAL TROUBLESHOOTING GUIDE No 12 V Check F301 Voltage 25 VA Check Adapter Check Q301 change NO YES NO Check R371 Voltage 12 VA Check R377 Voltage 12 V Check Q301 2pin Voltage 12 V Check IC302 YES YES YES NO NO OK OK ADAPTER POWER CIRCUIT YES ...

Page 48: ...d service purposes ELECTRICAL TROUBLESHOOTING GUIDE No VCC_5V USB_5V Check F301 Voltage 25 VA Check FB305 Voltage 5 1 VA Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check R378 Voltage 5 V Replace IC302 Replace IC306 YES YES NO NO OK ADAPTER POWER CIRCUIT ...

Page 49: ...d service purposes ELECTRICAL TROUBLESHOOTING GUIDE No HDMI_5 1VA Check F301 Voltage 25 VA Check FB305 Voltage 5 1 VA Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check C361 Voltage 3 3 V Replace IC302 Replace IC308 YES YES NO NO OK ADAPTER POWER CIRCUIT ...

Page 50: ...TROUBLESHOOTING GUIDE No D_3 3V PWM_3 3V Check F301 Voltage 25 VA Check FB305 Voltage 5 1 V A Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check R373 Voltage 3 3 VA Check FB307 FB313 Voltage 3 3 V Replace IC302 Replace IC301 Replace IC304 YES YES YES NO NO NO OK ADAPTER POWER CIRCUIT ...

Page 51: ...CTRICAL TROUBLESHOOTING GUIDE No WLS_3V3 Check F301 Voltage 25 VA Check FB305 Voltage 5 1 VA Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check R373 Voltage 3 3 VA Replace IC302 Replace IC301 YES YES NO NO Check C311 Voltage 3 3 V Replace IC309 YES NO OK ADAPTER POWER CIRCUIT ...

Page 52: ...CTRICAL TROUBLESHOOTING GUIDE ADAPTER POWER CIRCUIT No RBOX_3V3 Check F301 Voltage 25 VA Check FB305 Voltage 5 1 VA Check Adapter Replace IC305 YES YES YES NO NO Check R371 Voltage 12 VA Check R373 Voltage 3 3 VA Replace IC302 Replace IC301 YES YES NO NO Check C371 Voltage 3 3 V Replace IC310 YES NO OK ...

Page 53: ...ice purposes ELECTRICAL TROUBLESHOOTING GUIDE KEY PART Replace the cables Check R111 Pull up Resistor YES Check CN103 1 2 pin Voltage 3 3 V Check the connecting cables Check RA01 RA04 RA05 RA06 Replace the Related part YES NO Check SWA01 SWA02 SWA03 SWA04 OK YES YES NO NO OK 2 KEY PART ...

Page 54: ...nd service purposes ELECTRICAL TROUBLESHOOTING GUIDE USB PART Refer to Power Part Troubleshooting Check JK201 1pin Voltage 5 1 V YES Check R379 Voltage 5 1 V Check IC306 Check JK201 2pin D 3pin D Replace the Related part YES NO Check Reading OK OK YES YES NO NO OK 3 USB FUNCTION ...

Page 55: ...ce purposes ELECTRICAL TROUBLESHOOTING GUIDE OPTICAL FUNCTION Refer to Power Part Troubleshooting Check IC501 pin M19 Input waveform Check R587 Replace the related part YES NO OK 4 OPTICAL FUNCTION Replace the related part Check R549 3 3VA Voltage YES Check JK202 Check R202 YES YES NO NO ...

Page 56: ... 6 SF_CS 3 3VA SF_DI SF_CLK SF_DO DGND DGND C103 100nF R108 4 7K R110 4 7K R107 4 7K R106 4 7K R109 NC IC102 1 CS 2 SO 3 WP 4 VSS 5 SI 6 SCLK 7 HOLD 8 VCC 1 R506 1M NC X501 27MHz 1 IN OUT 2 FLOAT 3 ININ OUT 4 FLOAT R505 1 8K C563 15pF C564 15pF DGND Close to IC501 2 C600 8pF C620 8pF R601 1M R600 2 2K DGND X600 24 576MHz 1 INPUT OUTPUT 2 FLOAT 3 INPUT OUTPUT 4 FLOAT FIG 2 VCC CS CLK DO 3 4 5 6 VCC...

Page 57: ...MP_SD OTW DC_DETECT AMP_CLIP0 MTDO R163 100 MTMS R162 100 R161 100 R160 100 R159 100 R158 100 MTCK R120 0 R119 0 DOWNLOAD RESET MTDI IC101 89 P5 2 XT2IN 90 P5 3 XT2OUT 91 TEST SBWTCK 92 PJ 0 TDO 93 PJ 1 TDI TCLK 94 PJ 2 TMS 95 PJ 3 TCK 96 RST NMI SBWTDIO 97 P6 0 A0 98 P6 1 A1 99 P6 2 A2 100 P6 3 A3 R183 100 R184 100 DGND RA01 680 RA03 1K RA02 820 RA00 CA00 100nF SWA00 1 2 3 4 SWA01 1 2 3 4 SWA02 1...

Page 58: ...ses 4 USB FIG 4 1 USB 5 V FIG 4 2 USB D 8 9 FIG 4 3 USB D 10 9 8 10 C205 10pF NC USB_GND USB_5V USB_5V C206 10pF NC JK201 1 5V 2 USB D 3 USB D 4 DGND D D 2 0 2 C F u 0 1 3 0 2 C F u 0 1 C200 220uF NC DGND 1 0 2 C F n 0 0 1 USB1_DP USB1_DN FB201 1 2 3 4 D201 uCLAMP0561P R210 4 7 R211 4 7 USB MPEG ...

Page 59: ...Voltage 11 FIG 5 2 Low Timing 12 Item Measured Spec Input Level 3 3 V IR Receiver Spec 2 7 5 5 V Low Timing 4 4 ms 3 6 ms 5 04 ms High Timing 4 48 ms 4 08 ms 5 04 ms FIG 5 3 High Timing 13 13 12 11 IR RECEIVER REMOCON DGND C151 100nF R199 100 C150 100pF 3 3VA C152 10uF D101 Z02W3 9V 1 2 3 RC120 1 GND 2 VCC 3 OUT 4 GND REMO_TP IR ...

Page 60: ... reserved Only for training and service purposes 15 14 OPTICAL JACK 96KHz 3 3VA JK202 1 OUT 2 GND 3 VCC R209 82 R202 100 C208 15pF R201 560 DGND DGND OPT_IN OPT_DET C207 1uF C224 100pF MPEG MICOM OPTICAL 6 OPTICAL FIG 6 1 OPT IN 14 FIG 6 2 OPT DET 15 ...

Page 61: ...V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V V Vr r r r r r r r r r r r r r r r r r r r r r r r r r r r r r r r rm m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m ...

Page 62: ...31 V IC402 TUNER IC VA 11 VCC 2 7V 5 5V VCC 3 31 V IC501 IC Video Processors DVCC12_K DVCC12_K 1 14 V 1 26 V DVCC12_K 1 21 V DVCC33_IO DVCC33_IO 3 15 V 3 45 V DVCC33_IO 3 32 V DDRVCCIO1 DDRVCCIO1 1 425 V 1 575 V DDRVCCIO1 1 51 V AVDD33 AVDD33 3 15 V 3 45 V AVDD33 3 32 V AVDD12 AVDD12 1 14 V 1 26 V AVDD12 1 21 V AVDD12_LDO 1 14 V 1 26 V IC502 DDR3 SDRAM MEMORY VDD B2 D9 G7 K2 K8 VDD VDDQ 1 5 V 0 07...

Page 64: ...3 37 NC VOL VOL POWER FUCN EAX6850350 1 V ER1 3 S L4 SL5 KEY BO ARD FR4 2L 1 2 T 2 018 12 07 PCB SI ZE 40 6 X30 T P A 0 0 T P A 0 1 S W A 0 0 S W A 0 1 S W A 0 2 S W A 0 3 S W A 0 4 R A 0 0 R A 0 1 R A 0 2 R A 0 3 R A 0 4 R A 0 5 R A 0 6 C A 0 0 C N A 0 0 2 KEY P C BOARD DIAGRAM TOP VIEW BOTTOM VIEW ...

Page 66: ...IR GUIDE 4 2 1 NO POWER PROBLEM PVDD 4 2 2 POWER ON ERROR 4 3 3 POWER ON ERROR 4 4 4 WIRELESS CONNECTION 4 5 WAVEFORMS OF MAJOR CHECK POINT 4 6 1 VOLTAGE 4 6 2 AMP VOLTAGE 4 7 3 PWM 4 8 4 LED 4 9 WIRING DIAGRAM 4 11 BLOCK DIAGRAM 4 13 PRINTED CIRCUIT BOARD DIAGRAMS 4 15 1 WOOFER SMPS P C BOARD 4 15 2 WOOFER AMP P C BOARD 4 17 3 WOOFER KEY P C BOARD 4 17 ...

Page 67: ...olution If you check these points and find PVDD voltage is not checked replace woofer SMPS board 1 2 Service hint Any picture Remark Woofer AMP board bottom view Woofer AMP board top view PVDD PVDD pin3 4 5 6 at WCN601 pin3 4 5 6 at WCN601 PVDD PVDD pin7 at WIC606 pin7 at WIC606 Nearby WC610 Nearby WC610 PVDD PVDD pin7 at WIC607 pin7 at WIC607 Nearby WC686 Nearby WC686 PVDD PVDD at WCA601 at WCA60...

Page 68: ...s NG Replace WIC606 If you can t check PVDD voltage then you replace woofer SMPS board 2 2 3 7 VA 1 Check 3 7 VA at WL606 coil 2 If 3 7 VA is not checked at the point then find PVDD at pin7 of WIC607 3 1 2 is NG Replace WIC607 If you can t check PVDD voltage then you replace woofer SMPS board Woofer AMP board top view Woofer AMP board top view 12 V 12 V at WL604 at WL604 PVDD PVDD at pin7 of WIC60...

Page 69: ...603 and WL627 2 Check 3 3V_PWM at pin5 of WIC605 3 Check 3 3 VA at pin7 8 of WIC603 4 Check 3 3V_PWM at WL615 nearby WIC601 If all voltages are OK then check the PVDD voltage of woofer SMPS board Woofer AMP board top view 3 3V_PWM 3 3V_PWM at WL615 at WL615 3 3 VA 3 3 VA at WCA603 WL627 at WCA603 WL627 3 3 VA 3 3 VA at pin7 8 of WIC603 at pin7 8 of WIC603 3 3V_PWM 3 3V_PWM at pin5 of WIC605 at pin...

Page 70: ...reless Factory Reset MAIN SET Soundbar vol MIN and push Mute key sustain 3 5 sec Subwofer Push Pairing key on the back case of the wireless subwoofer The LED of of the wireless subwoofer blink red and green pull out power cord The main set and the wireless subwoofer are factory reset mode then power on Woofer KEY board top view Woofer AMP board top view 3 3 VA 3 3 VA at WL616 at WL616 Wireless mod...

Page 71: ...pyright 2021 LG Electronics Inc All rights reserved Only for training and service purposes WAVEFORMS OF MAJOR CHECK POINT 1 VOLTAGE FIG 1 1 WIC607 3 7 VA 1 FIG 1 2 PWM 3 3 V 2 FIG 1 3 Wireless 3 3 VA 3 3 2 1 ...

Page 74: ...4 9 Copyright 2021 LG Electronics Inc All rights reserved Only for training and service purposes 4 LED FIG 4 1 Pairing Off Status Red LED 8 FIG 4 2 Pairing On Status Yellow LED 9 9 8 ...

Page 76: ...nly for training and service purposes DIP 2pin SWF Harness Cable 12Pin FFC SMD 24 Pin straight Dip 2Pin Power Cord SMPS PCB AMP PCB Harness 12Pin Connector Pairing Key 2Pin Harness Cable 2Pin Pairing Key PCB LED CNT Wireless module 4 12 4 11 WIRING DIAGRAM ...

Page 77: ...ctronics Inc All rights reserved Only for training and service purposes WOOFER AMP PVDD WOOFER AMP SW LPF DC DC DC DC LDO PVDD PVDD PWM 3 3 Wireless 3 3 3 7 V LDO PWM PWM_SW PWM_SW 12 V SW LPF Flash 4 14 4 13 BLOCK DIAGRAM ...

Page 78: ...nc All rights reserved Only for training and service purposes 4 16 4 15 PRINTED CIRCUIT BOARD DIAGRAMS 1 WOOFER SMPS P C BOARD TOP VIEW BOTTOM VIEW NOTE Warning Parts that are critical with respect to risk of fire or electrical shock ...

Page 79: ...Copyright 2021 LG Electronics Inc All rights reserved Only for training and service purposes 4 18 4 17 2 WOOFER AMP P C BOARD 3 WOOFER KEY P C BOARD TOP VIEW TOP VIEW BOTTOM VIEW BOTTOM VIEW ...

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LG SN4A, Service Manual

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