Download Print this page
LG 24LM520S-WU Service Manual

LG 24LM520S-WU Service Manual

Hide thumbs Also See for 24LM520S-WU:

Advertisement

Quick Links

LED TV
SERVICE MANUAL
CHASSIS :
MODEL :
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
P/NO :
MFL70041057 (1901-REV00)
Copyright © 2019 LG Electronics Inc. All rights reserved. Only training and service purposes.
LB70B
24LM520S
CONFIDENTIAL
24LM520S-WU

Advertisement

loading

Summary of Contents for LG 24LM520S-WU

  • Page 1 LED TV SERVICE MANUAL CHASSIS : LB70B MODEL : 24LM520S 24LM520S-WU CAUTION BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. P/NO : MFL70041057 (1901-REV00) Copyright © 2019 LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 2 SERVICING PRECAUTIONS ..............4 SPECIFICATION ..................6 SOFTWARE UPDATE ................9 BLOCK DIAGRAM .................. 10 EXPLODED VIEW .................. 11 TROUBLE SHOOTING GUIDE ..........APPENDIX - 2 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 3: Safety Precautions

    When the exposed metal has no return path to the chassis the reading must be infinite. An other abnormality exists that must be corrected before the receiver is returned to the customer. - 3 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 4: Servicing Precautions

    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 - 4 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 5 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. - 5 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 6: Specification

    Rear 1EA H/P out Head phone out EMF, MPEG, For SVC Side 1EA USB Input(2EA) (download) JPEG, MP3, MPEG LAN port Rear 1EA - 6 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 7 1920 x 1080 56.25 50.00 HDTV 1080P(DVB) DVB Only 1920 x 1080 67.43 59.94 HDTV 1080P 1920 x 1080 67.5 60.00 HDTV 1080P - 7 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 8 1360 x 768 @60Hz 47.71 60.01 VESA(WXGA) 1280 x 1024 @60Hz 63.98 60.02 VESA(SXGA) FHD only 1920 x 1080 @60Hz 67.5 60.00 WUXGA(CEA 861D) FHD only - 8 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 9: Software Update

    1) Push "IN-START" key in service remote controller. 2) Select "Tool Option 1" and Push “OK” button. 3) Punch in the number. (Each model has their number.) - 9 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 10: Block Diagram

    BLOCK DIAGRAM - 10 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 11: 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. - 11 - Copyright © LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 12: Troubleshooting Guide

    TROUBLE SHOOTING GUIDE Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 13 Wrecked audio/discontinuation/noise Remote control & Local switch checking D. Function error External device recognition error E. Noise Circuit noise, mechanical noise F. Exterior error Exterior defect Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 14 ☞A3 & A6 Always check & record S/W Version and White Replace Main Board Re-enter White Balance value Balance value before replacing the Main Board Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 15 No video / No audio Revised date ☞A13 No video / Check voltage 19V Normal Replace Main No audio of Adaptor Voltage B/D or Repair parts Replace Adaptor Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 16 Tuner soldering Picture 1. Reconnection 2. Install Booster Replace S/W Upgrade Normal Contact with signal distributor Main B/D Picture or broadcaster (Cable or Air) Normal Picture Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 17 External ☞A10 Check external Compon device/ Check Test pattern device and Replace Main B/D ent, Cable cable HDMI Normal error Request repair for external device/cable Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 18 Main B/D (Component/AV/ error and HDMI by connecting HDMI) Jig, pattern Generator, Set-top Box etc. S/W Upgrade Request repair for external device Normal Screen Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 19 Stand-By : Red Check Adaptor/ Power cord was inserted properly Power LED On ※ ☞A16 Normal Check ST-BY 3.4V Voltage Replace Adaptor or Replace Main B/D Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 20 "POWEROFF_UNKNOWN" Power off by unknown status except listed case Power off by abnormal status except CPU trouble "POWEROFF_ABNORMAL1" Abnormal Power off by CPU Abnormal "POWEROFF_CPUABNORMAL" Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 21 Check user No audio Connection Replace Speaker Connec Screen normal from Main  or Main B/D tion Speaker Cable Insert wafer SPK Cable Normal Audio Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 22 Normal Request repair to external Audio cable/ANT provider (In case of External Input Check and fix external device signal error) Check and fix external device Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 23 When turn off light Baterry of R/C in room If R/C operate, Explain the customer Normal cause is interference Operating from light in room. Replace R/C Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 24 Input - Fix information information Recognition error - S/W Version Fix in Check and fix accordance HDMI external device/cable with technical Recognition error information Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 25 KMS fix information and then proceed as the process by stage. shown in the solution manual (For models without any fix information, provide the description) Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 26 Revised date Zoom part with Module Replace module exterior damage damage Cabinet Replace cabinet damage Remote control Replace remote control damage Stand Replace stand damage Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 27 A-2/5 <Appendix> Exchange LED driver Board (PSU) A-3/5 Defected Type caused by T-Con/ Inverter/ Module Exchange Module itself (1) A-4/5 Exchange Module itself (2) A-5/5 Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 28 Checking method in Setting when there is no C. Audio error_No audio/Normal video audio D. Function error_ No response in remote Remote control operation checking method control, key error Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 29 A. Video Error, No Video/Normal Audio Established date Content Check Back Light On with Naked eye Revised date Power On -> disjoint back case -> check lighting Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 30 A. Video Error, No Video/Normal Audio Established date Content Main Board to LED back light Voltage Revised date Measure DC Voltage applying to LED backlight from Main B/D Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 31 2. Enter into White Balance of item 11 3. After recording the R, G, B (GAIN, Cut) value of Color Temp (Cool/Medium/Warm), re-enter the value after replacing the MAIN BOARD Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 32 A. Video Error, No Video/Normal Audio Established date Content Power Voltage Measuring Method Revised date HD Model : 27 ~ 30 pin Check LVDS Voltage 12V Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 33 All Settings  Channels  Channel Tuning  Manual Tuning  Select channel When the signal is strong, use the attenuator (-10dB, -15dB, -20dB etc.) Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 34 Established date Content Version Checking Method Revised date Checking SW version method for remote control for adjustment Press the IN-START with the remote control for adjustment Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 35 Connection diagram Revised date As the part connecting to the external input, check the screen condition by signal * Jack spec. : depending on Model Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 36 A. Video Error, Color Error Established date Content Check and replace Link Cable(LVDS) and contact condition Revised date 1. Check and replace LVDS Cable 2. Check LVDS connection condition Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 37 You can view 10 types of patterns using the ADJ Key Checking item : 1. Defective pixel 2. Residual image 3. MODULE error (ADD-BAR,SCAN BAR..) 4.Video error (Classification of MODULE or Main-B/D) Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 38 T-Con Defect, CNT Broken Abnormal Power Section Solder defect, CNT Broken Solder defect, CNT Broken T-Con Defect, CNT Broken Abnormal Power Section Solder defect, Short/Crack Solder defect, Short/Crack Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 39 Appendix : Exchange T-Con Board (2) Abnormal Power Section Abnormal Power Section Solder defect, Short/Crack Abnormal Display Fuse Open, Abnormal power section Solder defect, Short/Crack Noise GRADATION GRADATION Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 40 Appendix : Exchange the Module (1) Press damage Press damage Press damage Un-repairable Cases In this case please exchange the module. Crosstalk Crosstalk Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 41 Gate TAB IC Defect Gate TAB IC Defect Un-repairable Cases In this case please exchange the module. Horizontal Block Gate TAB IC Defect Gate TAB IC Defect Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 42 Established date Content Check front Display LED Revised date ST-BY condition: Red Front LED control : All Settings  General  Standby Light  On/Off Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 43 Error Symptom B. Power Error, No Power Established date A12/ 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 Power off Mode checking method Revised date 1. Press the IN-START button of the remote control for adjustment 2. Check the entry into adjustment item 3 Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 45 LED_R ① < Sub Ass’y> < Main Ass’y> ② 1, 2. Check IR cable condition between IR & Main board 3. Check the 3.4V_ST Voltage Copyright © 2019 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 46 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.

This manual is also suitable for:

24lm520s24lm520swu