LG 42LN54 Series Service Manual

Hide thumbs Also See for 42LN54 Series:

Owner's manual (137 pages)

Service manual (76 pages)

Owner's manual (63 pages)

page of 76

/ 76
Bookmarks

Quick Links

Download this manual

LED TV

SERVICE MANUAL

CHASSIS : LD31B/LD36B

MODEL : 42LN54**

CAUTION

BEFORE SERVICING THE CHASSIS,

READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

P/NO : MFL67651302 (1310-REV01)

North/Latin America

Europe/Africa

Asia/Oceania

42LN54**-Z*

Internal Use Only

http://aic.lgservice.com

http://eic.lgservice.com

http://biz.lgservice.com

Printed in Korea

Need help?

Do you have a question about the 42LN54 Series and is the answer not in the manual?

Questions and answers

Summary of Contents for LG 42LN54 Series

Page 1 Internal Use Only North/Latin America http://aic.lgservice.com Europe/Africa http://eic.lgservice.com Asia/Oceania http://biz.lgservice.com LED TV SERVICE MANUAL CHASSIS : LD31B/LD36B MODEL : 42LN54** 42LN54**-Z* CAUTION BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. P/NO : MFL67651302 (1310-REV01) Printed in Korea...
Page 2 SPECIFICATION ..................6 ADJUSTMENT INSTRUCTION ............. 10 BLOCK DIAGRAM ................. 16 EXPLODED VIEW .................. 19 SCHEMATIC CIRCUIT DIAGRAM .............. - 2 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 3 An other abnormality exists that must be corrected before the receiver is returned to the customer. - 3 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only 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. - 5 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 6 HOTBIRD 6/8/9, EUTELSAT-SESAT, ASTRA 1L/H/M/ KR, ASTRA 3A/3B, BADR 4/6, ASTRA 2D, EUROBIRD 3, EUTELSAT-W7, HELLASSAT 2, EXPRESS AM1, TURK- SAT 2A/3A, INTERSAT10 - 6 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 7 LA58 : for DLNA Ethernet (1EA) DLNA(Wired, DMP only) T2 Model ( LA58V, LA58U, LN54V, LN54U ) : for MHEG - 7 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 8 HDTV 1080P 1920*1080 27.00 24.00 74.25 HDTV 1080P 1920*1080 26.97 23.976 74.176 HDTV 1080P 1920*1080 33.75 30.00 74.25 HDTV 1080P - 8 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 9 Side by Side, Top & Bottom 6.5. 3D Input mode Side by Side Top & Bottom Single Frame Sequential Frame Packing - 9 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 10 In this case, you have to channel recover. if all channel data is cleared, you didn’t have a DTV/ ATV test on production line. - 10 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 11 MODEL NAME(HEX) Enter Adjust When transfer the ‘Mode In’, LG TV 00 00 00 FC 00 4C 47 20 54 56 0A 20 20 20 20 20 20 20 (LG TV) Adjust MODE ‘Mode In’ Carry the command. Automatically adjustment e.
Page 12 R-Gain. - In this case, increasing/decreasing of B Gain and R Gain can be adjusted. RS-232C Communication - 12 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 13 (2) When 3D OSD appear automatically , then select OK key. Result) If, The LED light is green and the Module shows normal stream → OK, Else → NG - 13 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 14 Data : Write data CS : CMD + LENGTH + ADH + ADL + Data_1 +...+ Data_n Delay : 20ms - 14 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 15 (3) Play Test (F9) button and confirm OK Message. ▪ Check the OK or NG (4) Remove LAN cable. - 15 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 19 X-RADIATION, Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer. - 19 - Copyright © LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 20 2012/07/05 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. MAIN1_EU_OS Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 21 2012/07/05 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. MAIN2_EU_OS Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 22 2012/09/19 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR Power_PD2 THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 23 2012/07/18 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR IR/CONTROL THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 24 NC4_S7LRM 12/06/20 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 25 FILRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR HDMI_R1_S1 THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 26 12/06/12 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR SPDIF THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 27 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR M1_DDR (2DDR) THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 28 2012/06/20 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR S_FLASH_OS THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 29 2012/06/20 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR HEADPHONE THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 30 2012/06/19 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. PCMCI Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 31 FILRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 32 2012/06/19 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR TUNER_EU THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 33 FILRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 34 FILRE AND ELECTRICAL SHOCK HAZARDS, WHEN SERVICING IF IS ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR AMP_STA380BWEF THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 35 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR MSTAR DEBUG_4PIN THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 36 2012/06/20 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR RS232C_4P_OS THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 37 2012/06/22 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR LVDS_EU THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 38 2012/06/19 ESSENTIAL THAT ONLY MANUFATURES SPECFIED PARTS BE USED FOR REAR_JACK_EU THE CRITICAL COMPONENTS IN THE SYMBOL MARK OF THE SCHEMETIC. Copyright © 2013 LG Electronics. Inc. All rights reserved. LGE Internal Use Only Only for training and service purposes...
Page 40 Always check & record S/W Version and White Replace Main Board Re-enter White Balance value Balance value before replacing the Main Board Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 41 Power Board Normal No Video/ replace No audio voltage? ( 3.5V,12V,20V or 24V…) MAIN B/D Replace Power Board and repair parts Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 42 2. Install Booster S/W Upgrade Normal Contact with signal distributor Replace or broadcaster (Cable or Air) Picture? Main B/D Normal Picture? Close Close Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 43 Change satellite setting signal distributor Normal (match with installed ANT) or broadcaster Picture? (Cable or Air) Normal Picture? Close Close Close Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 44 Request repair for external device/cable Check external RGB/ External device device and Replace Main B/D HDMI/DVI /Cable cable error normal Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 45 HDMI Normal External Input, Component, Replace and HDMI by connecting Jig, screen? Screen pattern Generator ,Set-top Box Main B/D normal? etc. Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 46 Measure voltage of each output of Power B/D Normal? ※ Normal Replace Main B/D voltage? Close Normal Check ST-BY 3.5V voltage? ☞A12 Replace Power B/D Replace Power Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 47 Power off by unknown status except listed case "POWEROFF_ABNORMAL1" Power off by abnormal status except CPU trouble Abnormal "POWEROFF_CPUABNORMAL" Power off by CPU Abnormal Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 48 Screen normal voltage Speaker off Cancel OFF Replace Power Board and repair parts Check Speaker Replace MAIN Board Disconnection disconnection Replace Speaker Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 49 Input signal error) Connect and check Normal Check and fix other external device audio? external device Check and fix external device Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 50 (Power B/D don’t have problem) Normal If R/C operate, Close operating? Explain the customer cause is interference from light in room. Replace R/C Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 51 - S/W Version RGB,HDMI/ Check and fix DVI, Optical Replace Main B/D Fix in external device/cable Recognition error accordance with technical information Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 52 “Part related to nose” in the Owner’s Manual. (For models without any fix information, provide the description) Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 53 Zoom part with Module Replace module exterior damage damage Cabinet Replace cabinet damage Remote Replace remote controller controller damage Stand Replace stand dent Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 54 Defected Type caused by T-Con/ Inverter/ Module Exchange Module itself (1) A-4/5 Exchange Module itself (2) A-5/5 Continue to the next page Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 55 Voltage and speaker checking method in audio/discontinuation case of audio error D. Function error_ No response in Remote controller operation checking method remote controller, key error Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 56 Check Back Light On with naked eye date <ALL MODELS> Power On -> disjoint back case -> check lighting at 2 points. Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 57 Module from Power Board. 93.2~118.5V Output 93.2~118.5V from Power Board -> supply to Module. Check Pin contacting statement and connection statement. Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 58 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 © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 59 Check the DC 24V, 12V, 3.5V. 18 Pin (Power Board ↔ Main Board) - Common Power on DRV ON 3.5V PDIM#1 3.5V PDIM#2 Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 60 MENU => Press red key Remote controller=>signal test => Select channel When the signal is strong, use the attenuator (-10dB, -15dB, -20dB etc.) Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 61 <ALL MODELS> 1. Checking method for remote controller for adjustment Version Press the IN-START with the remote controller for adjustment Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 62 LCD TV connection diagram (1) date <ALL MODELS> As the part connecting to the external input, check the screen condition by signal Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 63 Check and replace Link Cable(LVDS) and contact condition date <ALL MODELS> 1. Check and replace LVDS Cable 2. Check LVDS connection condition Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 64 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 © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 65 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 © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 66 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 © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 67 Appendix : Exchange PSU(LED driver) No Light Dim Light Dim Light Dim Light No picture/Sound Ok Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 68 Panel Mura, Light leakage Press damage Crosstalk Press damage Crosstalk Un-repairable Cases In this case please exchange the module. Press damage Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 69 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 © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 70 Revised Content Check front display LED date Front LED control : Menu  Option  Standby light ON ST-BY condition: Red Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 71 Check the DC 24V, 12V, 3.5V. 18 Pin (Power Board ↔ Main Board) - Common Power on DRV ON 3.5V PDIM#1 3.5V PDIM#2 Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 72 Check the DC 24V, 12V, 3.5V. 18 Pin (Power Board ↔ Main Board) - Common Power on DRV ON 3.5V PDIM#1 3.5V PDIM#2 Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 73 Entry method 1. Press the IN-START button of the remote controller for adjustment 2. Check the entry into adjustment item 3 Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes LGE Internal Use Only...
Page 74 2. Select the AUDIO function of the Menu 3. Select Sound Out – TV Speaker *If you set Sound-Out menu as External Speaker/LG Sound Sync, TV Speaker will not work. Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes...
Page 75 ③ 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 © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes...
Page 76 When checking the Pre-Amp when the power is in ON condition, it is normal when the Analog Tester needle moves slowly, and defective when it does not move at all. Copyright © 2013 LG Electronics. Inc. All rights reserved. Only for training and service purposes...

This manual is also suitable for:

42ln54 z series 42ln5406-za