LG SJ4Y Service Manual Download Page 75

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5-4

Only for training and service purposes.

ONE POINT REPAIR GUIDE

1. How to Duplicate Problem

Wireless rear speaker doesn’t output a sound.

1-1.

Solution

Replace SMPS board (No PVDD).

1-2. How to troubleshoot (Countermeasure)

2. How to Duplicate Problem

Wireless rear speaker doesn’t output a sound.

2-1.

Solution

Replace AMP board (No 12 V).

2-2. How to troubleshoot (Countermeasure)

2-3. Service hint (Any picture / Remark)

Check LED color of RX BOX.

Try to remate or reset.

Color is yellow?

Replace SMPS board.

YES

RIC307

RIC308

RIC307

RIC308

< AMP board top view >

Replace AMP board.

Check 3.3 V.

YES

Replace SMPS board.

14 VA

(RIC308 pin2)

no input.

AMP 12 V

(RIC308 pin4)

no output.

YES

Summary of Contents for SJ4Y

Page 1: ...E UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL CONFIDENTIAL MODEL SJ4Y SJ4Y SPJ4B W P NO AFN78302533 FEBRUARY 2019 MODEL SJ4Y SJ4Y SPJ4B W Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes Wireless Sound Bar ...

Page 2: ... 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 OPTION ...

Page 3: ... training and service purposes SECTION 1 GENERAL CONTENTS ESD PRECAUTIONS 1 3 NAME OF EACH COMPONENT 1 4 WIRELESS SUBWOOFER CONNECTION 1 5 REAR SPEAKERS CONNECTION SOLD SEPARATELY 1 6 ABOUT LED CONDITION 1 7 HIDDEN KEY MODE 1 8 SOFTWARE UPDATE GUIDE 1 9 SPECIFICATIONS 1 15 ...

Page 4: ...assified 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 toget...

Page 5: ...LED Red C Qzshynts WPO bmnyj D The buttons are located on the rear A o p atqzrj Liozxyx tqzrj qj jq F Qzshynts jqjhyx ymj kzshynts fsi nsuzy xtzwhj 1 yfsig Zs B DC IN LN fifuyjw nsuzy C OPTICAL IN Zuynhfq nsuzy D PORTABLE IN twyfgqj nsuzy E USB F HDMI OUT TV ARC IN SOXT tzyuzy nsuzy NAME OF EACH COMPONENT Front Panel Rear Panel ...

Page 6: ...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 green LED on the rear of the wireless subwoofer blinks quickly 2 Turn on the main unit 3 Pairing is completed The green LED on the rear of the wireless subwoofer turns on Note It takes a few seconds and may take longer for th...

Page 7: ...eless receiver LED Color Status 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 wil...

Page 8: ...tssjhynts WR _a WPO yzwsx ts WR tzsi sh bnwjqjxx kzshynts nx xjqjhyji HDMI IN WPO yzwsx ts SOXT TY kzshynts nx xjqjhyji WR _a fsi SOXT TY WPOx yzws ts Z _LMWP kzshynts nx xjqjhyji USB and BT Bluetooth LEDs yzws ts L N kzshynts nx xjqjhyji y bmjs tz uwjxx fs gzyyts0 xyfsig LED Red ts ymj rfns zsny gqnspx y bmjs tz uwjxx Xzyj gzyyts0 xyfsig WPO ji gqnspx xqt q y bmjs ymnx zsny wjfhmjx rnsnrzr tqzrj0...

Page 9: ...minimum state Main unit F Function for 7 seconds Exit Main unit F Function for 7 seconds TV Remote control On Off On Press and hold REAR LEVEL on the remote control for about 2 seconds Off Press and hold REAR LEVEL and press it once again while ON TV REMOTE is scrolled Display window ON TV REMOTE OFF TV REMOTE BT Lock On Off On Press and hold AUTO POWER ON on the remote control for about 2 seconds...

Page 10: ..._SJ4 BIN if USB driver is E MEQ E MEQ BIN if USB driver is E PEQ E EQ_PRG BIN if USB driver is E OPTION E OPT BIN if USB driver is E WOOFER WIRELESS TX E WIRELESS_TX bin if USB driver is E WOOFER WIRELESS RX E WIRELESS_RX bin if USB driver is E REAR WIRELESS TX E WIRELESS_REAR_TX BIN if USB driver is E REAR WIRELESS RX E WIRELESS_REAR_RX BIN if USB driver is E 1 2 Update 1 Power on 2 Select the US...

Page 11: ...lectronics Inc All rights reserved Only for training and service purposes 2 2 Connect Bluetooth Connected 2 1 Run BT App Music Flow Bluetooth Not Connected 2 Using APP FOTA Firmware update Over The Air Connection button Menu button ...

Page 12: ...tting Menu Connected 2 4 1 FOTA Start Button Phone should be available internet Wi Fi LTE 3G Internet not Connected Some Country ex China can not access to CDN Server And can not use FOTA So This Button can not enable in that country Using APP FOTA Firmware update Over The Air Setting button FOTA Start button ...

Page 13: ...017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 2 5 FOTA Caution Using APP FOTA Firmware update Over The Air 2 4 2 FOTA Start Button Internet Connected OK button FOTA Start button ...

Page 14: ...erved Only for training and service purposes Using APP FOTA Firmware update Over The Air 2 6 FOTA CDN Download Cancel Button is available When CDN downloading 2 7 FOTA OPP Download Cancel Button is not available When OPP downloading Cancel button Cancel button ...

Page 15: ...onics Inc All rights reserved Only for training and service purposes Using APP FOTA Firmware update Over The Air 2 8 FOTA Write Flash Cancel Button is not available When Flash writing 2 9 FOTA Finish Cancel button Power cable reconnect ...

Page 16: ...UT 19 Pin Type A HDMI connector x 1 AMPLIFIER RMS OUTPUT Total 300 W RMS Front 60 W RMS x 2 4 Ω at 1 kHz THD 10 Subwoofer 180 W RMS 3 Ω at 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 180 W RMS Max Input Power 360 W RMS Dim...

Page 18: ...ng and service purposes SECTION 2 CABINET MAIN CHASSIS CONTENTS DISASSEMBLY INSTRUCTIONS 2 2 1 HOW TO DISASSEMBLE THE MAIN UNIT 2 2 2 HOW TO DISASSEMBLE THE WOOFER 2 8 EXPLODED VIEWS 2 11 1 MAIN UNIT SECTION 2 11 2 WIRELESS SUBWOOFER SECTION 2 13 3 PACKING ACCESSORY SECTION 2 15 ...

Page 19: ... DISASSEMBLY INSTRUCTIONS 1 1 2 3 Figure 1 1 1 HOW TO DISASSEMBLE THE MAIN UNIT Before begin position the Main Unit upside down 1 1 Case Bottom Assembly 1 Remove the 19 screws 2 Remove the Case Bottom Assembly 3 Remove the 2p harness cable key connected to the MAIN PCB Assembly Case Bottom Assembly KEY ...

Page 20: ...raining and service purposes 3 2 1 Figure 1 2 2 Figure 1 2 1 HOW TO DISASSEMBLE THE MAIN UNIT 2 Remove the screw 3 Remove the Main Frame Assembly Main Chassis PCBA 1 2 Main Frame Assembly 1 Disconnect the 2 harness cables from the Main PCB Assembly Main Frame Assembly FL FR ...

Page 21: ... 2 HOW TO DISASSEMBLE THE MAIN UNIT 1 2 1 Front PCB Assembly 1 Remove the 2 screws 2 Remove the Front PCB Assembly 1 2 2 Main PCB Assembly 1 Detach the cables from the Main chassis 2 Disconnect the FFC cables from the Main PCB 3 Remove the 3 screws Main HDMI Jack 4 Remove the Main PCB Assembly Front PCB Assembly Main PCB Assembly Main Chassis ...

Page 22: ... 4 5 4 Figure 1 2 3 1 2 3 BT and WIRELESS Module 1 Disconnect the FFC cable from the BT module 2 Remove the BT module 3 Disconnect the FFC cable from the WIRELESS module 4 Disconnect the 2 Hooks 5 Remove the WIRELESS module 6 Disconnect the FFC cable from the WIRELESS module 7 Remove the WIRELESS module BT Module WIRELESS Module WIRELESS Module ...

Page 23: ... purposes 1 2 Figure 1 4 Figure 1 3 HOW TO DISASSEMBLE THE MAIN UNIT 1 4 KEY PCB Assembly 1 Remove the 2 screws 2 Remove the Key PCB Assembly 1 3 SPEAKER CHAMBER L R Assembly 1 Remove the Speaker Chamber L R Assembly Speaker Chamber Left Assembly Speaker Chamber Right Assembly Key PCB Assembly ...

Page 24: ...urposes Figure 1 5 1 Speaker network cable from SPK Chamber L R Assembly to MAIN PCB Figure 1 5 2 Harness cable from KEY PCB to MAIN PCB HOW TO DISASSEMBLE THE MAIN UNIT 1 5 How to organize cables When assembling place the cables Speaker network cables and Key cable as shown in the figure below ...

Page 25: ...ts reserved Only for training and service purposes Figure 2 1 1 Figure 2 1 2 2 HOW TO DISASSEMBLE THE SUBWOOFER 2 1 Rear Panel Assembly 1 Remove the 13 screws 2 Pull out the Rear Panel Assembly and disconnect the SPK cable Rear Panel Assembly SPK cable ...

Page 26: ... FFC cable 2 Remove the EVA sheet 0 15T covered the WIRELESS module 3 Remove the WIRELESS module 4 Remove the EVA gasket 1 0T covered the WIRELESS module Caution when assembling the WIRELESS Module 1 Attach the EVA gaskets 1 0T to both sides of the WIRELESS module 2 Assemble the WIRELESS module into the wireless holder 3 Attach the EVA sheet 0 15T to the WIRELESS module 4 Connect the FFC cable AMP...

Page 27: ...ly for training and service purposes 1 2 Figure 2 3 1 Figure 2 3 2 HOW TO DISASSEMBLE THE SUBWOOFER 2 3 AMP SMPS PCB Assembly 1 Disconnect the Power inlet socket cable 2 Remove the 5 screws 3 Remove the AMP SMPS PCB Assembly AMP SMPS PCB Assembly AMP SMPS PCB Assembly ...

Page 28: ...rvice purposes FRONT MAIN E D C A B A43 A46 F A55 267 C 262 A44 B T A54 A52 CABLE2 D CABLE3 KEY A41 B A E F 253 CABLE1 A80R 285 287 287 285 272 272 271R 271L A42 254 288 288 254 WIRELESS 264 277 277 278 277 A80L G WIRELESS A54 265 G CABLE4 2 12 2 11 EXPLODED VIEWS 1 MAIN UNIT SECTION ...

Page 29: ...Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 951 B A A 954 953 956 958 A900 A900W B A45W A54W 952 960 960 961 2 14 2 13 2 WIRELESS SUBWOOFER SECTION ...

Page 30: ...t 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 300 Power cord 833 AC adapter 900 Remote control 836 Screws 2 835 Wall bracket 806 Optical cable 3 PACKING ACCESSORY SECTION ...

Page 32: ... DOESN T BOOTING WHEN YOU TURN ON THE SET 3 5 2 NO SOUND 3 8 3 PROTECTION ERROR 3 13 WAVEFORMS OF MAJOR CHECK POINT 3 16 1 CRYSTAL 3 16 2 FLASH MEMORY 3 16 3 TACT KEY 3 17 4 USB 3 18 5 REMOTE CONTROL 3 19 6 OPTICAL 3 20 7 PORTABLE 3 21 CIRCUIT VOLTAGE CHART 3 23 1 IC VOLTAGE 3 23 2 CAPACITOR VOLTAGE 3 24 3 CONNECTOR VOLTAGE 3 24 PRINTED CIRCUIT BOARD DIAGRAMS 3 25 1 MAIN P C BOARD DIAGRAM 3 25 2 F...

Page 33: ...poses MAIN FR4 Epoxy 4layer 1 2T 234x59 5 Array size 242x133 FRONT CEM 1 1 6T 128 5x55 Array size 257x128 Wireless BT CN101 CN102 CN107 12P FFC 26P FFC CN704 CN703 5P Harness 4P Harness SPK FL SPK FR CN103 2P Harness KEY CEM 1 1 6T CNK01 Rear Wireless CN108 26P FFC 12P B to B CNF02 WIRING DIAGRAM ...

Page 34: ... HDMI OUT BT_SPDIF KEY FL 40 W AMP TL 20 W PWM_RST MUTE I2C_DAT I2C_CLK M_BCK LRCK DATA0 1 2 FR P N TWR P N PWM_DATA2 LRCK BCK Potable in Analog_L R ADC PTB_DET PWM IC AMP FL 40 W LPF TL 20 W FL P N TWL P N Key PCB Serial Flash SPI Adapter 25 V Wireless Active Woofer 200 W Rear SPK 120 W Front PCB Dot LED 5ea IR Receiver BT_UART SPDIF USB1 TMDS HPD I2C ARC CEC TMDS RX_HPD I2C PWR5V CEC BT_RESET ST...

Page 35: ...T Module RCU OPTICAL DCDC DCDC Switching TR 12 V 1 2 V 5 1 VA 3 3 VA 1000mA 100mA PWM Switch WL_CTRL P_CTRL P_CTRL P_CTRL 10mA 100mA 10mA 10mA 100mA 100mA PWM_3 3 V USB LCD 1100mA VCC_5 V Switch 3 3 VA 3 3 VA Ctrl_VCC Alive VCC LDO or Switch DCDC DCDC 5 V MICOM 1 5 V 1 5 V Switch D_3 3 V 100mA 20mA 100mA 12 V 3 3 VA 3 3 VA Switch WL_CTRL 350mA DSP DDR D33_CTRL 2 POWER BLOCK DIAGRAM ...

Page 36: ...t LED doesn t work 1 1 IC302 System 12 VA No 12 VA 1 1 1 Solution Replace MAIN board 1 1 2 How to troubleshoot Countermeasure 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 IC302 IC302 IC302 IC302 L302 L302 ...

Page 37: ...N ON THE SET Front LED doesn t work 1 2 IC301 System 3 3 V No 3 3 VA 1 2 1 Solution Replace MAIN FRONT board 1 2 2 How to troubleshoot 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 FRONT board 1 2 3 Service hint Any picture Remark MAIN board top view IC301 IC301 IC301 IC301 L301 L301 ...

Page 38: ...RN ON THE SET Front LED doesn t work 1 3 LED System power 5 V 3 3 VA No 5 V 3 3 VA 1 3 1 Solution Replace MAIN FRONT board 1 3 2 How to troubleshoot Countermeasure 1 Please check 3 3 VA 5 V of CNF02 pin10 pin6 2 If 3 3 VA 5 V is abnormal replace MAIN board 3 If 3 3 VA 5 V OK replace FRONT board 1 3 3 Service hint Any picture Remark FRONT board bottom view ...

Page 39: ...n Replace MAIN board 2 1 2 How to troubleshoot Countermeasure 1 Please check status of Bluetooth cable connection at CN102 and BT module 2 Please check 3 3 VA at pin1 of CN102 If 3 3 V is OK please check BT_RST BT_SPDIF BT_RX BT_TX pin2 4 11 12 If no signal please replace MAIN board 2 1 3 Service hint Any picture Remark MAIN board top view CN102 CN102 CN102 CN102 ...

Page 40: ...GUIDE NO SOUND 2 2 OPTICAL 2 2 1 Solution Replace MAIN board 2 2 2 How to troubleshoot 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 R209 R209 C208 C208 ...

Page 41: ...IR GUIDE NO SOUND 2 3 HDMI 2 3 1 Solution Replace MAIN board 2 3 2 How to troubleshoot Countermeasure 1 Please check soldering status of HDMI jack and check HDMI_5 1VA 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 bottom view IC308 IC308 ...

Page 42: ...O SOUND 2 4 PORTABLE 2 4 1 Solution Replace MAIN board 2 4 2 How to troubleshoot Countermeasure 1 Please check the soldering status of portable jack and check IC201 pin3 VCC_5V pin4 D_3 3V 2 If portable jack and voltage has abnormal status replace MAIN board 2 4 3 Service hint Any picture Remark MAIN board top view IC201 IC201 ...

Page 43: ... GUIDE NO SOUND 2 5 USB 2 5 1 Solution Replace MAIN board 2 5 2 How to troubleshoot Countermeasure 1 Please check USB Jack and FB201 soldering status And check 5 V at JK201 pin1 2 If soldering status and voltage has abnormal status replace MAIN board 2 5 3 Service hint Any picture Remark MAIN board top view FB201 FB201 ...

Page 44: ...lace MAIN board 3 1 2 How to troubleshoot Countermeasure 1 Check DC Voltage of speaker out FL TWL CN703 pin1 2 3 4 and 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 AR60...

Page 45: ...untermeasure 1 Check PVDD voltage 25 V of IC700 IC701 pin38 37 36 If PVDD voltage has 8 5 V under refer to STEP 1 1 2 Check GVDD VDD voltage 12 V of IC700 IC701 pin1 2 If GVDD VDD voltage has 8 5 V under refer to STEP 1 1 3 Check impedance 4 Ω of speaker unit If impedance of speaker unit has 1 Ω under replace speaker unit 4 If check point 1 2 3 is ok replace MAIN board 3 2 3 Service hint Any pictu...

Page 46: ...ION ERROR No display or No Sound 3 3 B BURNT PROTECTION 3 3 1 Solution Replace MAIN board 3 3 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 3 3 Service hint Any picture Remark MAIN board bottom view IC701 IC701 IC700 IC700 ...

Page 47: ...lectronics Inc All rights reserved Only for training and service purposes WAVEFORMS OF MAJOR CHECK POINT 1 CRYSTAL FIG 1 1 X501 27 MHz 1 FIG 1 2 X600 24 576 MHz 2 2 FLASH MEMORY FIG 2 VCC CS CLK DO 3 4 5 6 VCC CS CLK DO 6 5 3 4 1 2 ...

Page 48: ...G Electronics Inc All rights reserved Only for training and service purposes 3 TACT KEY FIG 3 2 Press FUNC Key 0 72 0 82 V FIG 3 1 Press Power Key 1 1 13 V 7 7 FIG 3 3 Press VOL Key 0 424 0 485 V 7 FIG 3 4 Press VOL Key 0 V 7 7 ...

Page 50: ...nly for training and service purposes 5 REMOTE CONTROL FIG 5 1 Input 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 12 13 11 ...

Page 52: ...Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 7 PORTABLE FIG 7 1 ADC IC 5 V 16 FIG 7 2 ADC IC 3 3 V 17 FIG 7 3 Analog Input Voltage 1 1 27 Vrms 18 16 17 18 ...

Page 54: ...95 C A1 A8 C1 C9 D2 E9 F1 H2 H9 VDDQ 1 5 V 0 075 V 1 51 V IC503 IC NOR Flash Memory 8 VCC 2 7 V 3 6 V 3 32 V 85 C IC600 IC Sound Audio Processor 17 52 VDD_IO 2 97 V 3 63 V 3 33 V 85 C 6 25 VDD_CORE 1 08 V 1 32 V 1 24 V 34 VIN33_REG1 2 97 V 3 63 V 3 33 V 66 VIN33_REG2 2 97 V 3 63 V 3 3 V 68 VDD_PLL 1 08 V 1 32 V 1 24 V IC700 IC Audio Amplifier 1 GVDD_AB 0 3 V 13 2 V 11 7 V 125 C 22 GVDD_CD 0 3 V 13...

Page 55: ...Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 3 26 3 25 PRINTED CIRCUIT BOARD DIAGRAMS 1 MAIN P C BOARD DIAGRAM TOP VIEW BOTTOM VIEW ...

Page 56: ...Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 3 28 3 27 2 FRONT P C BOARD DIAGRAM 3 KEY P C BOARD DIAGRAM TOP VIEW TOP VIEW BOTTOM VIEW BOTTOM VIEW ...

Page 58: ...CONTENTS WIRING DIAGRAM 4 2 BLOCK DIAGRAM 4 3 ONE POINT REPAIR GUIDE 4 4 1 POWER ON ERROR 4 4 2 WIRELESS CONNECTION 4 6 WAVEFORMS OF MAJOR CHECK POINT 4 7 1 CRYSTAL 4 7 2 FLASH MEMORY 4 7 3 VOLTAGE 4 8 4 AMP VOLTAGE 4 9 5 PWM 4 10 6 LED 4 11 CIRCUIT VOLTAGE CHART 4 13 PRINTED CIRCUIT BOARD DIAGRAMS 4 15 1 WOOFER SMPS AMP P C BOARD 4 15 ...

Page 59: ...Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 2P 3 96mm ST Non Lock SMD 26P 0 5mm ST Non Lock SMD Wireless 2P 3 96mm ST Non Lock SMD Power WIRING DIAGRAM ...

Page 60: ... 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes PWM IC Wireless TX Wireless RX FL LPF AMP IC FR LPF AMP_PDN SW SW AMP_SD I2S I2C Reset KEY PAIRING LED RED GREEN BLOCK DIAGRAM ...

Page 61: ...e point then find PVDD at pin7 of WIC704 3 1 2 is NG Replace WIC704 If you can t check PVDD voltage then replace the PCB board 1 2 3 3 VA 1 Check 3 3 VA at WL707 coil 2 If 3 3 VA is not checked at the point then find 12 VA at pin3 of WIC705 3 1 2 is NG Replace WIC705 If you can t check 12 VA voltage refer to the step 1 1 Woofer SMPS AMP board top view Woofer SMPS AMP board top view WL708 WL708 WIC...

Page 62: ...e purposes WIC703 WIC703 ONE POINT REPAIR GUIDE POWER ON ERROR Fundamental power check points 1 3 3 3 VA 1 Check 3 3 VA at pin1 of WIC703 2 Check 3 3V_PWM at pin6 of WIC703 3 1 2 is NG Replace WIC703 If you can t check PVDD voltage then replace the PCB board Woofer SMPS AMP board bottom view ...

Page 63: ...connection closely 2 Implement Wireless Factory Reset MAIN SET Soundbar vol MIN and push Mute key sustain 3 5 seconds Subwofer Press Pairing button on the rear 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 SMPS AMP board top view WFB604 WFB604 Wireless module...

Page 64: ...17 2019 LG Electronics Inc All rights reserved Only for training and service purposes WAVEFORMS OF MAJOR CHECK POINT 1 CRYSTAL 2 FLASH MEMORY FIG 1 WX601 24 576 MHz FIG 2 VCC CS CLK DO 1 2 4 3 5 VCC CS CLK DO 1 2 4 5 3 ...

Page 65: ...pyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 3 VOLTAGE FIG 3 2 Woofer 12 VA FIG 3 1 Woofer PVDD 6 7 FIG 3 3 Woofer 3 3 VA 8 FIG 3 4 Woofer 3 3V_PWM 9 7 6 8 9 ...

Page 68: ...4 11 Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes 6 LED FIG 6 2 Pairing On Status Green LED FIG 6 1 Pairing Off Status Red LED 14 15 15 14 ...

Page 70: ... 68 VDD_PLL 1 08 V 1 32 V 1 28 V 1 28 V WIC701 IC Audio Amplifier PVDD 29 30 31 36 37 38 PVDD 12 V 34 V 20 61 V 20 64 V GVDD 1 22 GVDD 10 8 V 13 2 V 12 41 V 12 42 V VDD 2 VDD 10 8 13 2V 12 47 V 12 47 V WIC703 IC Analog Switch VIN 1 VIN 2 8 V 5 5 V 3 42 V 3 42 V VOUT 6 VOUT 2 8 V 5 5 V 3 41 V 3 41 V WIC704 IC DC DC Converter VIN 7 VIN 4 5 V 45 V 34 61 V 34 64 V SW 1 VOUT 0 8 V 42 V 12 53 V 12 53 V ...

Page 71: ...nc All rights reserved Only for training and service purposes 4 16 4 15 PRINTED CIRCUIT BOARD DIAGRAMS 1 WOOFER SMPS AMP P C BOARD TOP VIEW BOTTOM VIEW NOTE Warning Parts that are critical with respect to risk of fire or electrical shock ...

Page 72: ...vice purposes SECTION 5 WIRELESS RECEIVER PART OPTION CONTENTS WIRING DIAGRAM 5 2 BLOCK DIAGRAM 5 3 ONE POINT REPAIR GUIDE 5 4 ELECTRICAL TROUBLESHOOTING GUIDE 5 5 WAVEFORMS 5 7 PRINTED CIRCUIT BOARD DIAGRAMS 5 9 1 WIRELESS RECEIVER SMPS P C BOARD 5 9 2 WIRELESS RECEIVER AMP P C BOARD 5 11 ...

Page 73: ...pyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes Rear AMP SMPS Wireless RCN301 CN901 RJK301 SPK RR RL 26P FFC R C N 3 0 3 10P Harness SPK terminal WIRING DIAGRAM ...

Page 74: ... 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes PWM IC Wireless TX Wireless RX RL LPF AMP RR LPF AMP_PDN RL RR AMP_SD I2S I2C R Reset KEY PAIRING LED RED GREEN BLOCK DIAGRAM ...

Page 75: ...ermeasure 2 How to Duplicate Problem Wireless rear speaker doesn t output a sound 2 1 Solution Replace AMP board No 12 V 2 2 How to troubleshoot Countermeasure 2 3 Service hint Any picture Remark Check LED color of RX BOX Try to remate or reset Color is yellow Replace SMPS board YES NO RIC307 RIC307 RIC308 RIC308 RIC307 RIC308 AMP board top view NO Replace AMP board Check 3 3 V YES Replace SMPS bo...

Page 76: ...ireless rear speaker doesn t output a sound 3 1 Solution Replace AMP board No 3 3 V 3 2 How to troubleshoot Countermeasure 3 3 Service hint Any picture Remark RIC307 RIC307 RIC308 RIC308 RIC307 RIC308 AMP board top view NO Replace AMP board Check Module or connection YES Replace SMPS board 5 VA RIC307 pin2 no input PWM 3 3 V RIC307 pin3 no output YES NO ...

Page 77: ...e or Connection Yellow LED blinks irregularly Sound cut off irregularly Red LED is turned on LED is Red Turn off the equipment that gives interference Turn off the equipment that gives interference interference interference Remate Remate Check SMPS board AMP PVDD RCN301 pin9 10 no output Check RIC308 AMP 12 V RIC308 pin4 no output Check RIC307 3 3 V RIC307 pin3 no output YES YES YES YES YES YES YE...

Page 78: ...Copyright 2017 2019 LG Electronics Inc All rights reserved Only for training and service purposes RCN303 pin1 I2S LRCK RCN303 pin3 I2S BCK 1 2 WAVEFORMS 1 AUDIO PART I2S RCN303 pin20 I2S Audio Data 3 3 1 2 ...

Page 80: ...All rights reserved Only for training and service purposes PRINTED CIRCUIT BOARD DIAGRAMS 1 WIRELESS RECEIVER SMPS P C BOARD TOP VIEW BOTTOM VIEW 5 9 5 10 NOTE Warning Parts that are critical with respect to risk of fire or electrical shock ...

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