Download
Share
Print this page
LG 75UN8100PTB Service Manual
  1. Manuals
  2. Brands
  3. LG Manuals
  4. LED TV
  5. 75UN8100PTB
  6. Service manual

LG 75UN8100PTB Service Manual

Hide thumbs

Advertisement

Quick Links

Download this manual
LED TV
SERVICE MANUAL
CHASSIS : UBX3E
MODEL : 75UN8100PTB
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
P/NO : MFL71710511 (2002-REV00)
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, without limitation, any text, graphics or logos in this Service
Manual.
Copyright © 2020 LG Electronics Inc. All rights reserved. Only training and service purposes.

Advertisement

loading

Related Manuals for LG 75UN8100PTB

Summary of Contents for LG 75UN8100PTB

  • Page 1 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, without limitation, any text, graphics or logos in this Service Manual.
  • Page 2 SPECIFICATION ..................6 SOFTWARE UPDATE ................10 BLOCK DIAGRAM ................. 11 EXPLODED VIEW .................. 12 ASSEMBLY / DISASSEMBLY GUIDE ........... 13 TROUBLE SHOOTING GUIDE ..........APPENDIX - 2 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 3 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 training and service purposes.
  • Page 4 - 4 - Copyright © LG Electronics Inc. All rights reserved. Only 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. Only training and service purposes.
  • Page 6 PAL, SECAM, NTSC 4 System : PAL, SECAM, NTSC, PAL60 Audio Input DVI Audio, Component, AV 10 SPDIF out Optical Audio out Ethernet Connect - 6 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 7 1920*1080 56.25 148.5 HDTV 1080P 1920*1080 67.43 59.94 148.35 HDTV 1080P 1920*1080 67.5 148.5 HDTV 1080P 1920*1080 112.5 UDTV 2160P Not Support for FHD. - 7 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 8 107.89 23.98 1188 7680*4320 1188 7680*4320 1188 7680*4320 131.87 29.97 1188 8K Model Only. 7680*4320 1188 7680*4320 2376 7680*4320 263.74 59.94 2376 7680*4320 2376 - 8 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 9 241.5 Support only when UHD DeepColor is On (UHD, 8K 120Hz models 2560*1440 182.99 119.99 497.7 only), Support only when UHD DeepColor is On - 9 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 10 (6) Turn OFF the TV and On. Check the updated SW Version (8) After TV turned on, Check the updated SW Version and and Tool Option. Tool Option. - 10 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 11 BLOCK DIAGRAM - 11 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 12 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. - 12 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 13 ASSEMBLY / DISASSEMBLY GUIDE [Back Cover Disassembly Guide] 1. Latch Position and Structure (1) Latch Mechanism Latch Section A-A (2) Latch Position - 13 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 14 (If you lift it up too much, latch of B/C can be damaged) (2) Siding to top direction and you can disassemble it. (3) Complete disassemble of Back Cover. Sliding direction Module Latch assemble point - 14 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 15 Latch 4EA Power Cord Bracket 2. Unlock screw(“2”: 1 EA, ”3”: 8 EA, “4”:4 EA, “5”:4 EA) to separate back cover assem- bly from module. - 15 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 16 Insert the screwdriver into the hole and remove it by tilting it in the direction of the arrow. * Please use the driver with a diameter of 4.5mm or less. - 16 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 17 (5) MAIN P5800 → SPEAKER “C” → SPEAKER “D” 6. Unlock screw (“9”: 8 EA) to separate power PCB & main PCB from module. - 17 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 18 7. Separate speaker(2 EA) from module. Speaker Speaker 8. Detach Insulation sheet from module Do remove the bracket[10] after remove the sdcrew.[“11” 4 EA] Insulation Sheet - 18 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 19 Separate IR Assy from bottom bracket of latch. Separate connector “14”. Separate ac Combo PCB from bottom bracket of latch(2 EA). IR Assy Latch Latch Latch - 19 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 20 *top 10ea / side L 6ea / side R 6ea / down 10 EA Step 5) Disassemble the Panel. * Use a tape to fix the FFC - 20 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 21 Step 8) Disassemble the DPS, LED Array Fixer(pin), and the Reflector. * Rotate the DPS to * Push the LED remove (16 EA) Fixer (5 EA) - 21 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 22 (2) Press the surface of the LED Array to fix. (3) Connect the CNT to the LED Array. * Finish the Attached LED Array (5 EA) - 22 - Copyright © LG Electronics Inc. All rights reserved. Only training and service purposes.
  • Page 23 TROUBLE SHOOTING GUIDE Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 24 E. Noise Circuit noise, Mechanical noise F. Exterior error Exterior defect First of all, Check whether there is SVC Bulletin in GSCS System for these model. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 25 Always check & record S/W Version, White Replace Main Board Re-write Tool option, Area option and White Balance value Balance value before replacing the Main Board Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 26 Revised date ☞A18 Check 13.2V from Check and No video Normal Power B/D replace Main B/D No audio voltage? Replace Power B/D or repair parts Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 27 Bulletin? soldering 1. Reconnection 2. Install Booster S/W Upgrade Contact with signal distributor Normal Replace or broadcaster (Cable or Air) Picture? Main B/D Normal Picture? Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 28 Replace Main/T-con B/D device and cable error normal Request repair for external device/cable External Check external HDMI Replace Main/T-con B/D device/cable error device and cable normal Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 29 Screen (Check normal operation of HDMI Main /T-con normal? External Input, Component, AV and HDMI by connecting Jig, pattern Generator ,Set- top Box etc. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 30 Measure voltage of each output of Power B/D Normal? Normal ☞A18 Replace Main B/D voltage? Normal Check St-by 7.8V voltage? Replace Power B/D Replace Power B/D Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 31 Normal? Abnormal Check for all 2- phase Replace Power B/D power out No Poling Fix A/C cord & Outlet and check each 2 phase out Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 32 Reboot by SW down load function UNKNOWN No meaning (same as initial value) COMP_END OLED threshold voltage degradation(Compensation) completes. PNWASHDONE Power off by panel noise wash function complited. (OLED) Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 33 Check Speaker Disconnection Replace Speaker or cable Normal connection Reassemble Speaker and cable Replace Main B/D Normal Replace Speaker or cable Normal Replace Main B/D Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 34 (In case of Connect and check Normal External Input other external audio? signal error) device Check and fix external device Check and fix external device Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 35 Baterry of R/C Replace Power B/D in room If R/C operate, Normal operating? Explain the customer cause is interference from light in room. Replace R/C Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 36 RF Receiver message? Ver is about 5sec “00.00”? Replace MR20 Replace the RF Receiver assy * If you conduct the loop at 3times, change the MR20. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 37 1pin of Wi-Fi wafer Main B/D INSTART menu “NG”? ☞A23 Check & Repair Wi-Fi cable connection ☞A4 Wi-Fi Mac value is “NG”? Replace the Wi-Fi assy Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 38 Recognition error - S/W Version HDMI, Optical Check and fix Recognition Replace Main B/D Fix in external device/cable error accordance with technical information Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 39 “Part related to nose” in the Owner’s then proceed as shown in the solution manual Manual. (For models without any fix information, provide the description) Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 40 Revised date Zoom part with Module Replace module exterior damage damage Cabinet Replace cabinet damage Remote control Replace remote control damage Stand Replace stand dent Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 41 Exchange Module (1) ~ (3) A-8/11 A-9/11 ~ Only for using Exchange T-Con (1) ~ (2) T-con board A-10/11 Exchange Power Board(PSU) A-11/11 Continue to the next page Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 42 Motion Remote operation checking method How to use the Factory SVC Remote control A24-A26 E. Etc Check items after Main B/D replacement Adjustment Test pattern - ADJ Key Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 43 Check back light with naked eye date After disassembling a back cover and turning on TV, check with the naked eye, whether you can see light from locations. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 44 2. Enter into ‘11. White Balance’. 3. After recording the R, G, B value(Gain, Cut) of each Color Temp (Cool/Medium/Warm), write the value after replacing a Main board. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 45 When the signal is strong, use the attenuator (-10dB, -15dB, -20dB etc.) All Settings  Programmes  Programme Tuning & Settings  Manual Tuning Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 46 A. Video error_Video error, video lag/stop symptom date Revised Content Version checking method date Version Press ‘IN START’ button of the on Factory SVC Remote control. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 47 1. Check the signal strength or check whether the screen is normal when the external device is connected. 2. After measuring each voltage from power supply, finally replace the Main board. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 48 Revised Content Connection diagram date As the part connecting to the external input, check the screen condition by signal Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 49 A. Video error_Color error symptom date Revised Check Link Cable(Vx1 or EPI/CEDS) Content date reconnection condition Check connect condition of the Link Cable, especially dust or misassembling. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 50 Screen darkness to disconnection of the FFC cable pin. G color transient due to poor FFC cable CABLE G Color Excessive connection A - 1/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 51 CABLE Color spread FFC connection problem CABLE Color spread FFC connection problem Due to foreign substance within CABLE Screen stop FFC PIN A - 2/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 52 Main IC problem Main Dark picture Dark left-side screen Top/bottom screen part Main Broken picture Picture problem due to tuner Inner side quality problem A - 3/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 53 Screen spread Screen corner appears blurry Main Color Spread Color spread on the screen Main Blurry Screen Blurry picture on the screen A - 4/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 54 Screen picture spread problem Screen problem No problem at the initial stage. Right-side Main During Heat run, right-side picture picture problem problem A - 5/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 55 BLU internal foreign matter inflow MODULE Internal matter 6 block image broken MODULE Image broken MODULE Image broken Screen sync signal broken A - 6/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 56 BLU Vertical spreading on cube screen in no MODULE Vertical smear signal MODULE Over color Screen contour part brightly Over color A - 7/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 57 Center of the screen 1 block dark MODULE Screen darkness MODULE Vertical bar Center Vertical Bar Darkness at the MODULE bottom of the MODULE internal BLU breakage screen A - 8/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 58 T-Con is defective and the picture below T-CON image broken the screen is broken A - 9/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 59 The entire screen is dark and bit noise T-CON Image Broken occurs The entire screen is dark and bit noise T-CON Image Broken occurs A - 10/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 60 Appendix : Exchange Power Board (PSU) No Light No picture/Sound Ok A - 11/11 Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 61 Check Power Indicator in front date ST-BY condition : On or Off (Depending on ‘Standby Light’ setting in Additional Settings) Power On condition : Turn Off Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 62 Store mode : use Store 5. LED voltage Check : P801, LED B+ SK100 (AC input) Power Board is no problem if all the conditions are satisfied. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 63 POWER OFF MODE checking method date 1. Press ‘IN START’ button of the Factory SVC Remote control. 2. Check the entry into ‘3. Power On/Off Status’. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 64 1. Press the Setting button on the remote control. 2. Select the Sound function of the Menu. 3. Select the Sound Out. 4. Select Internal TV Speaker. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 65 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 © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 66 2. Check the +3.5V_ST on the terminal 22 pin. 3. As checking the Pre-Amp on IR/LED board, the power is in ON condition, an Analog Tester needle should move slowly, otherwise, it’s defective. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 67 [ Wi-Fi/BT board : Rear ] LED_R +3.5V_ST KEY2 1. Check connect condition between Wi-Fi/BT board and Main board. 2. Check +3.5V_WIFI on the terminal 1, 6, 12. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 68 Error Established E. Etc symptom date Revised Content How to use the Factory SVC Remote control date 1. How to access Factory SVC Remote control. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 69 Digital EYE function ON/OFF For some Model, access to the Test Pattern TILT Used for screen tilting change (Access to the old PDP control mode) Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 70 AV1,2,3 (Added function) Change to AV 1,2,3 COMP1,2 (Added function) Change to Component 1,2 HDMI1,2,3,4 (Add function) Change to HDMI 1,2,3,4 DVI (Add function) Change to DVI Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 71 - Record the R, G, B (GAIN, Cut) value of the color temperature before main board replacement. After replacing the main board, key in the recorded value. Copyright © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.
  • Page 72 You can view 9 types of patterns using ‘ADJ’ button 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 © 2020 LG Electronics. Inc. All rights reserved. Only for training and service purposes.

This manual is also suitable for:

Mfl7171051175un8100ptb caution