background image

No audio 

Screen normal 

Check user  

Connection 

from Main 

 

Speaker Cable 

Insert wafer SPK Cable 

Replace Speaker 

or Main B/D 

Connec

tion 

Error Symptom 

C. Audio Error 

Established date 

8/13 

Content 

No audio / Normal video 

Revised date 

Standard Repair Process 

A15 

Normal 

Audio 

End 

Copyright ©  2019  LG Electronics. Inc. All rights reserved.

Only for training and service purposes.

Summary of Contents for 24LM520S

Page 1: ...ERVICING THE CHASSIS READ THE SAFETY PRECAUTIONS IN THIS MANUAL SERVICE MANUAL CONFIDENTIAL MFL70041057 1901 REV00 24LM520S 24LM520S WU LB70B LED TV Copyright 2019 LG Electronics Inc All rights reserved Only training and service purposes ...

Page 2: ... Inc All rights reserved Only for training and service purposes CONTENTS CONTENTS 2 SAFETY PRECAUTIONS 3 SERVICING PRECAUTIONS 4 SPECIFICATION 6 SOFTWARE UPDATE 9 BLOCK DIAGRAM 10 EXPLODED VIEW 11 TROUBLE SHOOTING GUIDE APPENDIX ...

Page 3: ... the set is safe to operate without damage of electrical shock Leakage Current Cold Check Antenna Cold Check With the instrument AC plug removed from AC source connect an electrical jumper across the two AC plug prongs Place the AC switch in the on position connect one lead of ohm meter to the AC plug prongs tied together and touch other ohm meter lead in turn to each exposed metallic parts such a...

Page 4: ...y by touching a known earth ground Alternatively obtain and wear a commercially available discharging wrist strap device which should be removed to prevent potential shock reasons prior to applying power to the unit under test 2 After removing an electrical assembly equipped with ES devices place the assembly on a conductive surface such as aluminum foil to prevent electrostatic charge buildup or ...

Page 5: ...oints of the two original leads If they are not shiny reheat them and if necessary apply additional solder Fuse and Conventional Resistor Removal Replacement 1 Clip each fuse or resistor lead at top of the circuit board hollow stake 2 Securely crimp the leads of replacement component around notch at stake top 3 Solder the connections CAUTION Maintain original spacing between the replaced component...

Page 6: ...method 1 Performance LGE TV test method followed 2 Demanded other specification Safety CE IEC specification EMC CE IEC specification NOTE Specifications and others are subject to change without notice for improvement 4 MODEL General Specification No Item Specification Remarks 1 Market AMERICA CANADA MEXICO 2 Broadcasting system ATSC 3 Available Channel VHF 2 13 UHF 14 69 CATV 1 135 DTV 2 69 CADTV ...

Page 7: ...352 HDTV 1080P 5 2 HDMI EDID DATA Refer to adjust specification 5 2 1 DTV mode No Resolution H freq kHz V freq Hz Pixel clock MHz Remark 1 640 x 480 31 46 59 94 SDTV 480P 2 640 x 480 31 5 60 00 SDTV 480P 3 720 x 480 15 73 59 94 SDTV 480I Comment Only Spec Sheet Spec Out 4 720 x 480 15 75 60 00 SDTV 480I 5 720 x 576 15 62 50 00 SDTV 576I DVB 6 720 x 480 31 47 59 94 SDTV 480P 7 720 x 480 31 5 60 00 ...

Page 8: ... 640 x 350 70Hz 31 46 70 09 EGA 2 720 x 400 70Hz 31 46 70 08 DOS 3 640 x 480 60Hz 31 46 59 94 VESA VGA 4 800 x 600 60Hz 37 87 60 31 VESA SVGA 5 1024 x 768 60Hz 48 36 60 00 VESA XGA 6 1152 x 864 60Hz 54 34 60 05 VESA 7 1360 x 768 60Hz 47 71 60 01 VESA WXGA 8 1280 x 1024 60Hz 63 98 60 02 VESA SXGA FHD only 9 1920 x 1080 60Hz 67 5 60 00 WUXGA CEA 861D FHD only ...

Page 9: ...essage Copying files from memory 4 Updating is starting 5 Updating Completed The TV will restart automatically 6 If your TV is turned on check your updated version and Tool option explain the Tool option next stage If downloading version is more high than your TV have TV can lost all channel data In this case you have to channel recover if all channel data is cleared you didn t have a DTV ATV test...

Page 10: ...Micom I2C 3 IR KEY HDMI MUX LVDS USB SPDIF OUT ETHERNET USB1 OCP 1 5A HDMI1 HDMI2 ARC REAR R E A R Optical Digital Audio out LAN SYSTEM EEPROM 256Kb 30P eMMC 5 0 4GB DDR3 1066MHz 512MBx2EA I2C 1 X_TAL 24MHz WIFI Built in SUB ASSY USB_WIFI Tuner AV Component CVBS Y Pb Pr L R SIDE TU_CVBS TU_SCL SDA X_TAL 32 768KHz IR KEY TU_SIF SIFP I2C_2 ...

Page 11: ...acteristics These parts are identified by in the EXPLODED VIEW It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent Shock Fire or other Hazards Do not modify the original design without permission of manufacturer IMPORTANT SAFETY NOTICE 700 720 OR 730 200 300 831 570 540 541 400 401 900 120 832 500 LV1 AR1 ARC1 ...

Page 12: ...TROUBLE SHOOTING GUIDE Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 13: ...n off while viewing power auto on off 7 8 C Audio error No audio Normal video 8 9 Wrecked audio discontinuation noise 9 10 D Function error Remote control Local switch checking 10 11 External device recognition error 11 12 E Noise Circuit noise mechanical noise 12 13 F Exterior error Exterior defect 13 First of all Check whether there is SVC Bulletin in GSCS System for these model Contents of Stan...

Page 14: ...efore replacing the Main Board Replace Main Board Re enter White Balance value Precaution A4 A1 A2 A3 A6 First of all Check whether all of cables between board is inserted properly or not Main B D Adaptor LVDS Cable Speaker Cable IR B D Cable Normal Audio On Y N Normal Voltage Normal Voltage Y N Y N Error Symptom A Video Error Established date 1 13 Content No video Normal audio Revised date Standa...

Page 15: ... D or Repair parts Replace Adaptor Normal Voltage Y N Error Symptom A Video Error Established date 2 13 Content No video No audio Revised date Standard Repair Process A13 Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 16: ...g Diagnostics Setting on OSD Setting Customer Support red button on remote control Signal Test Signal strength Normal over 50 Signal quality Normal over 50 Y Contact with signal distributor or broadcaster Cable or Air N N Y N A6 End Normal Signal Normal Picture Normal Picture Normal Picture SVC Bulletin End End Normal Picture Error Symptom A Video Error Established date 3 13 Content Tuning fail Pi...

Page 17: ...ble Replace Main B D N A7 N Y Replace module Request repair for external device cable Check Test pattern A10 A8 A9 End Color error Color error External device Cable Normal External Input Compon ent HDMI error Error Symptom A Video Error Established date 4 13 Content Color error Revised date Standard Repair Process Copyright 2019 LG Electronics Inc All rights reserved Only for training and service ...

Page 18: ...Box etc N Y Replace Main B D Check screen condition by input External Input Component AV HDMI Request repair for external device Check S W Version Y N S W Upgrade Y N Y N Replace Main B D Replace Module A7 A8 A9 Check Test pattern N End Screen normal Screen normal Screen normal Screen normal Screen normal End End Check Version Normal Screen External Input error Error Symptom A Video Error Establis...

Page 19: ...ace Main B D N Y Check ST BY 3 4V N Replace Adaptor or Replace Main B D Y A11 A16 Stand By Red Power LED On Normal Voltage Normal Operati on Error Symptom B Power Error Established date 6 13 Content No power Revised date Standard Repair Process End Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 20: ...OWEROFF_RESREC Power off by Reservated Record POWEROFF_RECEND Power off by End of Recording POWEROFF_SWDOWN Power off by S W Download POWEROFF_UNKNOWN Power off by unknown status except listed case Abnormal POWEROFF_ABNORMAL1 Power off by abnormal status except CPU trouble POWEROFF_CPUABNORMAL Power off by CPU Abnormal Please refer to the all cases which can be displayed on power off mode Adaptor ...

Page 21: ...r SPK Cable Replace Speaker or Main B D Connec tion Error Symptom C Audio Error Established date 8 13 Content No audio Normal video Revised date Standard Repair Process A15 Normal Audio End Y N Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 22: ...rnal device Replace Main B D N A13 End Signal Normal Normal Voltage Normal Audio Wrecked Audio Discontinuation Noise for all audio Wrecked Audio Discontinuation Noise only for D TV Wrecked Audio Discontinuation Noise only for Analog Wrecked Audio Discontinuation Noise only for External Input N Replace Main B D Error Symptom C Audio Error Established date 9 13 Content Wrecked audio Discontinuation ...

Page 23: ...ck 3 4V On Main B D A16 N N Check Voltage 19V of Adaptor A13 Check IR Output signal N Y Replace IR B D N A16 Replace Main B D Y A16 End Normal Operating Normal Voltage Normal Signal Normal Operating Normal Operating End Y Error Symptom D Function Error Established date 10 13 Content Remote control Local switch checking Revised date Standard Repair Process Copyright 2019 LG Electronics Inc All righ...

Page 24: ...ith technical information Signal Input Technical information External Input and Component Recognition error HDMI Recognition error Error Symptom D Function Error Established date 11 13 Content External device recognition error Revised date Standard Repair Process Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 25: ...en proceed as shown in the solution manual For models without any fix information provide the description or Mechanical noise is a natural phenomenon and apply the 1st level description When the customer does not agree apply the process by stage Circuit noise Mechanical noise Error Symptom E Noise Established date 12 13 Content Circuit noise Mechanical noise Revised date Standard Repair Process Co...

Page 26: ...Replace stand Standard Repair Process Module damage Cabinet damage Remote control damage Stand damage Error Symptom F Exterior Defect Established date 13 13 Content Exterior defect Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 27: ...k Cable LVDS reconnection condition A8 A9 9 Adjustment Test pattern ADJ Key A10 10 11 A Video error_Vertical Horizontal bar residual image light spot Connection diagram A8 12 Check Link Cable reconnection condition A8 A9 13 Adjustment Test pattern ADJ Key A10 14 Appendix Defected Type caused by T Con Inverter Module Exchange T Con Board 1 A 1 5 15 Exchange T Con Board 2 A 2 5 16 Exchange LED drive...

Page 28: ...WER OFF MODE checking method A14 24 C Audio error_No audio Normal video Checking method in Setting when there is no audio A15 25 D Function error_ No response in remote control key error Remote control operation checking method A16 Contents of Standard Repair Process Detail Technical Manual First of all Check whether there is SVC Bulletin in GSCS System for these model Copyright 2019 LG Electronic...

Page 29: ...On disjoint back case check lighting Error Symptom A Video Error No Video Normal Audio Established date A1 Content Check Back Light On with Naked eye Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 30: ...age applying to LED backlight from Main B D Error Symptom A Video Error No Video Normal Audio Established date A2 Content Main Board to LED back light Voltage Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 31: ...e of Color Temp Cool Medium Warm re enter the value after replacing the MAIN BOARD Standard Repair Process Detail Technical Manual Error Symptom A Video Error No Video Normal Audio Established date A3 Content Check White Balance value Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 32: ...ck LVDS Voltage 12V Error Symptom A Video Error No Video Normal Audio Established date A4 Content Power Voltage Measuring Method Revised date HD Model 27 30 pin Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 33: ...e attenuator 10dB 15dB 20dB etc Standard Repair Process Detail Technical Manual Error Symptom A Video Error Video lag stop Established date A5 Content Tuner Input Signal Strength Checking Method Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 34: ...control for adjustment Press the IN START with the remote control for adjustment Error Symptom A Video Error No Video Normal Audio Established date A6 Content Version Checking Method Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 35: ...heck the screen condition by signal Jack spec depending on Model Error Symptom A Video Error Vertical Horizontal bar Residual Image Light spot Established date A7 Content Connection diagram Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 36: ...d Repair Process Detail Technical Manual Error Symptom A Video Error Color Error Established date A8 A9 Content Check and replace Link Cable LVDS and contact condition Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 37: ...fective pixel 2 Residual image 3 MODULE error ADD BAR SCAN BAR 4 Video error Classification of MODULE or Main B D Error Symptom A Video Error Color Error Established date A10 Content Adjustment Test Pattern ADJ Key Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 38: ...t CNT Broken Solder defect CNT Broken Solder defect CNT Broken Solder defect CNT Broken Abnormal Power Section Solder defect Short Crack Abnormal Power Section Solder defect Short Crack Appendix Exchange T Con Board 1 Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 39: ... Abnormal Power Section Solder defect Short Crack Fuse Open Abnormal power section Noise GRADATION GRADATION Abnormal Display Appendix Exchange T Con Board 2 Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 40: ...e Module 1 Crosstalk Crosstalk Press damage Press damage Un repairable Cases In this case please exchange the module Press damage Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 41: ... Vertical Block Source TAB IC Defect Horizontal Block Gate TAB IC Defect Horizontal line Gate TAB IC Defect Gate TAB IC Defect Horizontal Block Gate TAB IC Defect Appendix Exchange the Module 2 Un repairable Cases In this case please exchange the module Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 42: ...on Red Front LED control All Settings General Standby Light On Off Error Symptom B Power Error No Power Established date A11 Content Check front Display LED Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 43: ...al Error Symptom B Power Error No Power Established date A12 A13 Content Checking Method When Power is ON Revised date Check Voltage 19V of Adaptor Power Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 44: ...djustment item 3 Standard Repair Process Detail Technical Manual Error Symptom B Power Error Off when on off whiling viewing Established date A14 Content Power off Mode checking method Revised date Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 45: ... Sub Ass y Main Ass y Error Symptom D Function Error No Response in remote control Key error Established date A16 Content Remote control operation checking method Revised date P4101 1 3 4V_ST 2 KEY1 3 KEY2 4 GND 5 LED_R 6 NC 7 GND 8 IR Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

Page 46: ... there is no audio Revised date Main Ass y 1 Check the contact condition of DC jack or 19V input voltage from adapter 2 Connect the tester RX1 to the speaker terminal and if you hear the Chik Chik sound when you touch the GND and output terminal the speaker is normal Copyright 2019 LG Electronics Inc All rights reserved Only for training and service purposes ...

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