LG 23MA73D

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 : LA31A MODEL : 23MA73D 23MA73D-PUP CAUTION BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. P/NO : MFL67714439 (1301-REV00) Printed in Korea

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CONTENTS CONTENTS . ............................................................................................. 2 SAFETY PRECAUTIONS.......................................................................... 3 SERVICING PRECAUTIONS..................................................................... 4 SPECIFICATION........................................................................................ 6 ADJUSTMENT INSTRUCTION................................................................. 9 TROUBLE SHOOTING............................................................................ 13 BLOCK DIAGRAM................................................................................... 20 EXPLODED VIEW .................................................................................. 21 SCHEMATIC CIRCUIT DIAGRAM .............................................................. Copyright © LG Electronics. Inc. All right reserved. -2- LGE Internal Use Only Only for training and service purposes

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SAFETY PRECAUTIONS IMPORTANT SAFETY NOTICE Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the Schematic Diagram and 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. General Guidance Leakage Current Hot Check (See below Figure) Plug the AC cord directly into the AC outlet. An isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC Do not use a line Isolation Transformer during this check. power line. Use a transformer of adequate power rating as this Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor protects the technician from accidents resulting in personal injury between a known good earth ground (Water Pipe, Conduit, etc.) from electrical shocks. and the exposed metallic parts. Measure the AC voltage across the resistor using AC voltmeter It will also protect the receiver and it's components from being with 1000 ohms/volt or more sensitivity. damaged by accidental shorts of the circuitry that may be Reverse plug the AC cord into the AC outlet and repeat AC voltage inadvertently introduced during the service operation. measurements for each exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS which is corresponds to If any fuse (or Fusible Resistor) in this TV receiver is blown, 0.5mA. replace it with the specified. In case any measurement is out of the limits specified, there is possibility of shock hazard and the set must be checked and When replacing a high wattage resistor (Oxide Metal Film Resistor, repaired before it is returned to the customer. over 1W), keep the resistor 10mm away from PCB. Leakage Current Hot Check circuit Keep wires away from high voltage or high temperature parts. AC Volt-meter Before returning the receiver to the customer, always perform an AC leakage current check on the exposed Good Earth Ground such as WATER PIPE, metallic parts of the cabinet, such as antennas, terminals, etc., to CONDUIT etc. To Instrument's be sure the set is safe to operate without damage of electrical exposed 0.15µF shock. METALLIC PARTS Leakage Current Cold Check(Antenna Cold Check) 1.5 Kohm/10W With the instrument AC plug removed from AC source, connect an electrical jumper across the two AC plug prongs. Place the AC When 25A is impressed between Earth and 2nd Ground switch in the on position, connect one lead of ohm-meter to the AC for 1 second, Resistance must be less than 0.1 plug prongs tied together and touch other ohm-meter lead in turn to *Base on Adjustment standard each exposed metallic parts such as antenna terminals, phone jacks, etc. If the exposed metallic part has a return path to the chassis, the measured resistance should be between 1MΩ and 5.2MΩ. 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. Copyright © LG Electronics. Inc. All right reserved. -3- LGE Internal Use Only Only for training and service purposes

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SERVICING PRECAUTIONS CAUTION: Before servicing receivers covered by this service unit under test. manual and its supplements and addenda, read and follow the 2. After removing an electrical assembly equipped with ES SAFETY PRECAUTIONS on page 3 of this publication. devices, place the assembly on a conductive surface such as NOTE: If unforeseen circumstances create conflict between the aluminum foil, to prevent electrostatic charge buildup or following servicing precautions and any of the safety precautions on exposure of the assembly. page 3 of this publication, always follow the safety precautions. 3. Use only a grounded-tip soldering iron to solder or unsolder ES Remember: Safety First. devices. 4. Use only an anti-static type solder removal device. Some solder General Servicing Precautions removal devices not classified as "anti-static" can generate 1. Always unplug the receiver AC power cord from the AC power electrical charges sufficient to damage ES devices. source before; 5. Do not use freon-propelled chemicals. These can generate a. Removing or reinstalling any component, circuit board electrical charges sufficient to damage ES devices. module or any other receiver assembly. 6. Do not remove a replacement ES device from its protective b. Disconnecting or reconnecting any receiver electrical plug or package until immediately before you are ready to install it. other electrical connection. (Most replacement ES devices are packaged with leads c. Connecting a test substitute in parallel with an electrolytic electrically shorted together by conductive foam, aluminum foil capacitor in the receiver. or comparable conductive material). CAUTION: A wrong part substitution or incorrect polarity 7. Immediately before removing the protective material from the installation of electrolytic capacitors may result in an leads of a replacement ES device, touch the protective material explosion hazard. to the chassis or circuit assembly into which the device will be installed. 2. Test high voltage only by measuring it with an appropriate high CAUTION: Be sure no power is applied to the chassis or circuit, voltage meter or other voltage measuring device (DVM, and observe all other safety precautions. FETVOM, etc) equipped with a suitable high voltage probe. 8. Minimize bodily motions when handling unpackaged Do not test high voltage by "drawing an arc". replacement ES devices. (Otherwise harmless motion such as 3. Do not spray chemicals on or near this receiver or any of its the brushing together of your clothes fabric or the lifting of your assemblies. foot from a carpeted floor can generate static electricity 4. Unless specified otherwise in this service manual, clean sufficient to damage an ES device.) electrical contacts only by applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or comparable General Soldering Guidelines non-abrasive applicator; 10% (by volume) Acetone and 90% (by 1. Use a grounded-tip, low-wattage soldering iron and appropriate volume) isopropyl alcohol (90%-99% strength) tip size and shape that will maintain tip temperature within the CAUTION: This is a flammable mixture. range or 500 ˚F to 600 ˚F. Unless specified otherwise in this service manual, lubrication of 2. Use an appropriate gauge of RMA resin-core solder composed contacts in not required. of 60 parts tin/40 parts lead. 5. Do not defeat any plug/socket B+ voltage interlocks with which 3. Keep the soldering iron tip clean and well tinned. receivers covered by this service manual might be equipped. 4. Thoroughly clean the surfaces to be soldered. Use a mall wire- 6. Do not apply AC power to this instrument and/or any of its bristle (0.5 inch, or 1.25cm) brush with a metal handle. electrical assemblies unless all solid-state device heat sinks are Do not use freon-propelled spray-on cleaners. correctly installed. 5. Use the following unsoldering technique 7. Always connect the test receiver ground lead to the receiver a. Allow the soldering iron tip to reach normal temperature. chassis ground before connecting the test receiver positive (500 ˚F to 600 ˚F) lead. b. Heat the component lead until the solder melts. Always remove the test receiver ground lead last. c. Quickly draw the melted solder with an anti-static, suction- 8. Use with this receiver only the test fixtures specified in this type solder removal device or with solder braid. service manual. CAUTION: Work quickly to avoid overheating the circuit CAUTION: Do not connect the test fixture ground strap to any board printed foil. heat sink in this receiver. 6. Use the following soldering technique. a. Allow the soldering iron tip to reach a normal temperature Electrostatically Sensitive (ES) Devices (500 ˚F to 600 ˚F) Some semiconductor (solid-state) devices can be damaged easily b. First, hold the soldering iron tip and solder the strand against by static electricity. Such components commonly are called the component lead until the solder melts. Electrostatically Sensitive (ES) Devices. Examples of typical ES c. Quickly move the soldering iron tip to the junction of the devices are integrated circuits and some field-effect transistors and component lead and the printed circuit foil, and hold it there semiconductor "chip" components. The following techniques only until the solder flows onto and around both the should be used to help reduce the incidence of component component lead and the foil. damage caused by static by static electricity. CAUTION: Work quickly to avoid overheating the circuit 1. Immediately before handling any semiconductor component or board printed foil. semiconductor-equipped assembly, drain off any electrostatic d. Closely inspect the solder area and remove any excess or charge on your body by touching a known earth ground. splashed solder with a small wire-bristle brush. 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 Copyright © LG Electronics. Inc. All right reserved. -4- LGE Internal Use Only Only for training and service purposes

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IC Remove/Replacement CAUTION: Maintain original spacing between the replaced Some chassis circuit boards have slotted holes (oblong) through component and adjacent components and the circuit board to which the IC leads are inserted and then bent flat against the prevent excessive component temperatures. circuit foil. When holes are the slotted type, the following technique should be used to remove and replace the IC. When working with Circuit Board Foil Repair boards using the familiar round hole, use the standard technique Excessive heat applied to the copper foil of any printed circuit as outlined in paragraphs 5 and 6 above. board will weaken the adhesive that bonds the foil to the circuit board causing the foil to separate from or "lift-off" the board. The Removal following guidelines and procedures should be followed whenever 1. Desolder and straighten each IC lead in one operation by gently this condition is encountered. prying up on the lead with the soldering iron tip as the solder melts. At IC Connections 2. Draw away the melted solder with an anti-static suction-type To repair a defective copper pattern at IC connections use the solder removal device (or with solder braid) before removing the following procedure to install a jumper wire on the copper pattern IC. side of the circuit board. (Use this technique only on IC Replacement connections). 1. Carefully insert the replacement IC in the circuit board. 2. Carefully bend each IC lead against the circuit foil pad and 1. Carefully remove the damaged copper pattern with a sharp solder it. knife. (Remove only as much copper as absolutely necessary). 3. Clean the soldered areas with a small wire-bristle brush. 2. carefully scratch away the solder resist and acrylic coating (if (It is not necessary to reapply acrylic coating to the areas). used) from the end of the remaining copper pattern. 3. Bend a small "U" in one end of a small gauge jumper wire and "Small-Signal" Discrete Transistor carefully crimp it around the IC pin. Solder the IC connection. Removal/Replacement 4. Route the jumper wire along the path of the out-away copper 1. Remove the defective transistor by clipping its leads as close as pattern and let it overlap the previously scraped end of the good possible to the component body. copper pattern. Solder the overlapped area and clip off any 2. Bend into a "U" shape the end of each of three leads remaining excess jumper wire. on the circuit board. 3. Bend into a "U" shape the replacement transistor leads. At Other Connections 4. Connect the replacement transistor leads to the corresponding Use the following technique to repair the defective copper pattern leads extending from the circuit board and crimp the "U" with at connections other than IC Pins. This technique involves the long nose pliers to insure metal to metal contact then solder installation of a jumper wire on the component side of the circuit each connection. board. Power Output, Transistor Device 1. Remove the defective copper pattern with a sharp knife. Removal/Replacement Remove at least 1/4 inch of copper, to ensure that a hazardous 1. Heat and remove all solder from around the transistor leads. condition will not exist if the jumper wire opens. 2. Remove the heat sink mounting screw (if so equipped). 2. Trace along the copper pattern from both sides of the pattern 3. Carefully remove the transistor from the heat sink of the circuit break and locate the nearest component that is directly board. connected to the affected copper pattern. 4. Insert new transistor in the circuit board. 3. Connect insulated 20-gauge jumper wire from the lead of the 5. Solder each transistor lead, and clip off excess lead. nearest component on one side of the pattern break to the lead 6. Replace heat sink. of the nearest component on the other side. Carefully crimp and solder the connections. Diode Removal/Replacement CAUTION: Be sure the insulated jumper wire is dressed so the 1. Remove defective diode by clipping its leads as close as it does not touch components or sharp edges. possible to diode body. 2. Bend the two remaining leads perpendicular y to the circuit board. 3. Observing diode polarity, wrap each lead of the new diode around the corresponding lead on the circuit board. 4. Securely crimp each connection and solder it. 5. Inspect (on the circuit board copper side) the solder joints 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. Copyright © LG Electronics. Inc. All right reserved. -5- LGE Internal Use Only Only for training and service purposes

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SPECIFICATION NOTE : Specifications and others are subject to change without notice for improvement. 1. Application Range This spec sheet is applied all of the TV used LA31A chassis. 2. Specification Each part is tested as below without special appointment 1) Temperature : 25 ˚C ± 5 ˚C (77 ˚F ± 9 ˚F), CST : 40 ˚C ± 5 ˚C 2) Relative Humidity : 65 % ± 10 % 3) Power Voltage : Standard input voltage (100 V - 240 ­V ~, 50 / 60 Hz) · Standard Voltage of each products is marked by models 4) Specification and performance of each parts are followed each drawing and specification by part number in accord- ance with BOM. 5) The receiver must be operated for about 5 minutes prior to the adjustment. 3.Test method 1) Performance : LGE TV test method followed 2) Demanded other specification - Safety : CE,IEC specification - EMC : CE,IEC specification 4. General specification 4.1. TV No Item Specification Remarks 1 Market AMERICA, CANADA, MEXICO 2 Receiving system ATSC / NTSC-M / 64 & 256 QAM 3 Available Channel 1) VHF : 02~13 2) UHF : 14~69 3) DTV : 02-69 4) CATV : 01~135 5) CADTV : 01~135 4 Component Input (1EA) Y/Cb/Cr , Y/Pb/Pr 5. CVBS Input (1EA) NTSC 1 System(Rear) : NTSC CVBS Video input is used by common port with Component. 6 RGB Input RGB-PC Analog (D-SUB 15Pin) 7 HDMI Input (2EA) HDMI1/2 Rear / HDMI version 1.4/ support PC Support HDCP/HDMI2 : MHL Support 8 Audio Input (2EA) RGB/DVI Audio L/R Input Component & CVBS CVBS Audio input is used by common port with Component. 9 Earphone out (1EA) Antenna, AV, Component, RGB, HDMI1/2 10 Headphone out (1EA) Antenna, AV, Component, RGB, Side 1EA HDMI1/2 11 USB (1EA) EMF, DivX HD, Side 1EA For SVC (download) JPEG, MP3, DivX HD 12 Local Key (Touch) Copyright © LG Electronics. Inc. All right reserved. -6- LGE Internal Use Only Only for training and service purposes

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4.2. RGB(PC) Specification No Item Specification Remarks 1 Supported Sync. Type Separate Sync., Digital 2 Operating Frequency Analog Horizontal 30 ~ 83 kHz Vertical 56 ~ 75 Hz Digital Horizontal 30 ~ 83 kHz Vertical 56 ~ 75 Hz 3 Resolution Analog Max. 1920 x 1080 @ 60 Hz Recommend 1920 x 1080 @ 60 Hz Digital Max. 1920 x 1080 @ 60 Hz Recommend 1920 x 1080 @ 60 Hz 4 Operating Environment Temp : 10 ˚C ~ 35 ˚C Humidity : 20 % ~ 80 % 5 Storage Environment Temp : -10 ˚C ~ 60 ˚C non condensing Humidity : 5 % ~ 90 % non condensing 5. Timing 5.1. RGB/ HDMI (PC) No. Resolution H-freq(kHz) V-freq(Hz) Pixel clock(MHz) Remark 1 720*400 31.468 70.080 28.321 2 640*480 31.469 59.940 25.175 3 640*480 37.500 75.000 31.500 4 800*600 37.879 60.317 40.000 5 800*600 46.875 75.000 49.500 6 1024*768 48.363 60.004 65.000 7 1024*768 56.476 70.069 75.000 HDMI(PC) only 8 1024*768 60.023 75.029 78.750 9 1152*864 67.500 75.000 108.000 10 1280*720 45.000 60.000 74.250 11 1280*800 49.702 59.810 83.500 12 1280*1024 63.981 60.020 108.000 13 1280*1024 79.976 75.025 135.000 14 1400*1050 65.317 59.978 121.750 15 1440*900 55.935 59.887 106.500 16 1600*900 60.000 60.000 108.000 17 1680*1050 64.674 59.883 119.000 18 1680*1050 65.290 59.954 146.250 19 1920*1080 67.500 60.000 148.500 Copyright © LG Electronics. Inc. All right reserved. -7- LGE Internal Use Only Only for training and service purposes

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5.2. HDMI (DTV) No. Resolution H-freq(kHz) V-freq(Hz) Pixel clock(MHz) Remark 1 720* 480 31.469 / 31.5 59.94 / 60 27.00/ 27.03 SDTV 480P 2. 720*576 31.25 50.00 27.864 SDTV 576P 3. 1280*720 37.50 50.00 74.250 HDTV 720P 4 1280* 720 44.96 / 45 59.94 / 60 74.17/ 74.25 HDTV 720P 5 1920* 1080 33.72 / 33.75 59.94 / 60 74.17/ 74.25 HDTV 1080I 6 1920* 1080 28.125 50.00 74.25 HDTV 1080I 7 1920* 1080 27.00 24 74.25 HDTV 1080P 8 1920* 1080 33.75 30.00 74.25 HDTV 1080P 9 1920* 1080 56.250 50 148.5 HDTV 1080P 10 1920* 1080 67.43 / 67.5 59.94 / 60 148.35/ 148.50 HDTV 1080P 5.3. Component Specification No Remark Resolution H-freq(kHz) V-freq(Hz) Pixel clock( MHz) 1. 720* 480 15.73 59.94 13.500 SDTV, DVD 480I( 525I) 2. 720* 480 15.75 60.00 13.514 SDTV, DVD 480I( 525I) 3. 720* 576 15.625 50.00 13.500 SDTV, DVD 576I( 625I) 50Hz 4. 720* 480 31.47 59.94 27.000 SDTV 480P 5. 720* 480 31.50 60.00 27.027 SDTV 480P 6. 720* 576 31.25 50.00 27.000 SDTV 576P 50Hz 7. 1280* 720 44.96 59.94 74.176 HDTV 720P 8. 1280* 720 45.00 60.00 74.250 HDTV 720P 9. 1280* 720 37.50 50.00 74.25 HDTV 720P 50Hz 10. 1920* 1080 33.72 59.94 74.176 HDTV 1080I 11. 1920* 1080 33.75 60.00 74.250 HDTV 1080I 12. 1920* 1080 28.125 50.00 74.250 HDTV 1080I 50Hz 13. 1920* 1080 56.25 50 148.5 HDTV 1080P 14. 1920* 1080 67.432 59.94 148.350 HDTV 1080P 15. 1920* 1080 67.5 60.00 148.5 HDTV 1080P Copyright © LG Electronics. Inc. All right reserved. -8- LGE Internal Use Only Only for training and service purposes

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ADJUSTMENT INSTRUCTION 1. Application Range 4) Click “Read” tab, and then load download file(XXXX.bin) by clicking “Read” This document is applied to LA31A chassis TV which is manufactured in TV (or Monitor) Factory or is produced on the (4) basis of this data. filexxx.bin 2. Designation 1) The adjustment is according to the order which is designat- ed and which must be followed, according to the plan which can be changed only on agreeing. 2) Power adjustment : Free Voltage. 3) Magnetic Field Condition: Nil. 5) Click “Auto” tab and set as below 4) Input signal Unit: Product Specification Standard. 6) Click “Run”. 5) Reserve after operation: Above 5 Minutes (Heat Run) 7) After downloading, check “OK” message. Temperature : at 25 °C ± 5 °C Relative humidity : 65 % ± 10 % (5) Input voltage : 220 V, 60 Hz 6) Adjustment equipments : Color Analyzer (CA-210 or CA- (5) 110), DDC Adjustment Jig equipment, SVC remote control- ler. (7) ……….OK 7) Push The "IN STOP KEY" – For memory initialization Case1 : Software version up (6) 1) After downloading S/W by USB , Multi-vision set will reboot automatically 2) Push "In-stop" key 3) Push "Power on" key 4) Function inspection * USB DOWNLOAD(*.epk file download) 5) After function inspection, Push "In-stop" key. 1) Make New folder named “LG_DTV” and put ISP file(*.epk) in the folder. Case2 : Function check at the assembly line 2) Put the USB Stick to the USB socket. 1) When TV set is entering on the assembly line, Push "In- 3) Automatically detecting update file in USB Stick stop" key at first. - If your downloaded program version in USB Stick is 2) Push "Power on" key for turning it on. Low, it didn’t work. But your downloaded version is → If you push "Power on" key, TV set will recover channel High, USB data is automatically detecting. information by itself. 4) Show the message “Copy the file from the Memory…” 3) After function inspection, Push "In-stop" key. 3. Main PCB check process * APC - After Manual-Insult, executing APC 5) Updating is starting. * Boot file Download 1) Execute ISP program “Mstar ISP Utility” and then click “Config” tab. 2) Set as below, and then click “Auto Detect” and check “OK” message. If display “Error”, Check connect computer, jig, and set. 3) Click “Connect” tab. If display “Can’t ”, Check connect 6) Updating Completed, The TV will restart automatically. computer, jig, and set. 7) If your TV is turned on, check your updated version and (1) (3) Tool option. (explain the Tool option, next stage) * If downloading version is more high than your TV Please Check the Speed : have, TV can lost all channel data. In this case, you Use the speed under have to channel recover. if all channel data is cleared, 200KHz. you didn’t have a DTV/ATV test on production line. (2) OK Copyright © LG Electronics. Inc. All right reserved. -9- LGE Internal Use Only Only for training and service purposes

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3.1. EDID Process 3.1.2. RGB EDID Data 3.1.1. EDID download - 2D FHD (Check Sum : C1) 1) Press "Power only" key of service remote control. 2) Press the ADJ KEY on R/C and enter EZ ADJUST 3) Enter EDID D/L mode by pushing "►" key at "EDID D/L". 4) EDID download is executed automatically. 5) Press EXIT key on R/C. G WUG{––“Gv—›–•XG G G XUG{––“Gv—›–•YG G G YUG{––“Gv—›–•ZG G G ZUG{––“Gv—›–•[G G G [UG{––“Gv—›–•\G G G \UG{––“Gv—›–•]G G G *(week), **(year), ***(Check sum) : Adjustable Data ^UGh™ŒˆGv—›–•G _UGhkjGjˆ“‰™ˆ›–•G G G `UG~›ŒGiˆ“ˆ•ŠŒG XWUXWGw–•›G~iG G G G G lkpkGkVs G XXUG{Œš›Gwˆ››Œ™•G G G oktpX G vrG XYUGlkpkGkVsG G G G G G G G G G G G G ඖG XZUGzœ‰GiVjG G G G G oktpY yni G G vrG vrG 3.1.3. HDMI EDID Data X[UG{–œŠGzŒ•š›› GzŒ››•ŽG X\UGlŸ›UGp•—œ›Gh‹‘œš›G G G G z›ˆ™›G G yŒšŒ›G 1) HDMI1 (2D FHD - Check Sum: 15CE) G G G G → Caution: - Never connect HDMI & D-sub Cable when download EDID. -D ownload HDMI1, HDMI2 separately because HDMI1 is different from HDMI2. * Edid data and Model option download (USB) NO Item CMD CMD Data 0 1 2 Enter Download A A 0 0 When transfer the download ‘Mode In’ ‘Mode In’, MODE Carry the command. EDID data and Download A E 00 10 Automatically download Model option (The use of a internal download Data) 2) HDMI2 (2D FHD - Check Sum: 15BE) 3.2. Function Check 3.2.1. Check display and sound *Check Input and Signal items. (cf. work instructions) 1) TV 2) AV 3) COMPONENT (480i) 4) RGB(PC : 1920 x 1080 @ 60 Hz) 5) HDMI1/2 6) PC Audio In * Display and Sound check is executed by Remote controller → Caution : Not to push the INSTOP KEY after completion if the function inspection. Copyright © LG Electronics. Inc. All right reserved. - 10 - LGE Internal Use Only Only for training and service purposes

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4. Total Assembly line process 4.3. Function Check 4.1. Tool option & ADC Check 4.3.1. Check display and sound 1) Press "Power on" key of service remote control. *Check Input and Signal items. (cf. work instructions) 2) Connect USB Port → USB to Serial Adapter (UC-232A) → 1) TV RS-232C cable → PC(RS-232C port) 2) AV 3) Check the 'Tool Option' (Refer to the BOM Comments or 3) COMPONENT (480i) Adjustment spec) 4) RGB(PC : 1920 x 1080 @ 60 Hz) 4) Check the ‘ADC’ is ok. 5) HDMI1/2 6) PC Audio In 4.2. Model name & Serial number Down- * Display and Sound check is executed by Remote controller load → Caution : Not to push the INSTOP KEY after completion if the 4.2.1. Model name & Serial number D/L function inspection. 1) Press "Power on" key of service remote control. 2) Connect USB Port → USB to Serial Adapter (UC-232A) → RS-232C cable → PC(RS-232C port) 4.2.3. PIP Check 3) Write Model Name & Serial Number by use USB Port 1) Press "Power on" key of service remote control. 4) Must check the serial number at the Diagnostics of SET UP 2) Input RGB & TV(ATV or DTV) signal. menu. (Refer to below). 3) Set Input mode to RGB. 4) Press ‘PIP" key of ADJ remote controller 5) Check TV Video & Audio signal of Sub picture. 4.2.2. Method & notice 1) Model Name & Serial Number D/L is using of scan equip- ment. 2) Setting of scan equipment operated by Manufacturing Technology Group. 3) Serial number D/L must be conformed when it is produced 4.3.5 HDMI MHL Function Inspection.(HDMI2 Port in production line, because serial number D/L is mandatory only) by D-book 4.0 1) Insert HDMI cable for MHL function JIG connected to HDMI2 port of the SET. * Manual Download (Model Name and Serial 2) Check that LED of JIG is green light and check that set screen is correctly worked. Number) 3) If NG situation or other HDMI jack connection, LED of JIG If the TV set is downloaded By OTA or Service man, Some- is red light and screen is not displayed. times model name or serial number is initialized.( Not always) There is impossible to download by bar code scan, so It need Manual download. 1) Press the 'Instart' key of ADJ remote controller. 2) Go to the menu 'Model Number D/L' like below photo. 3) Input the Factory model name(ex 27MD73D-PZP) or Serial number like photo. 4) Check the model name Instart menu → Factory name displayed (ex 27MD73D-PZP) 5)Check the Diagnostics (DTV country only) → Buyer model displayed (ex 27MD73D-PZ) Copyright © LG Electronics. Inc. All right reserved. - 11 - LGE Internal Use Only Only for training and service purposes

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4.4. White balance adjustment 4.5. DPM Operation check RGB Gains are fixed data for each model. Insert RS-232C ■ Measurement Condition: 100~240V@ 50/60Hz Jack which is connected with PC for White Balance or equiva- 1) Set Input to RGB-PC and connect D-sub cable to set – lent device. RGB Mode. Color Cool 9,300k °K X=0.290 (±0.03) Set Input to HDMI1/2(with Input Label set to PC) and Temperature Y=0.298 (±0.03) Inner pattern connect HDMI1/2 cable to set – HDMI Mode (204gray,80IRE) Medium 8,000k °K X=0.300 (±0.03) 2) Cut off H sync or V sync of signal. Y=0.310 (±0.03) 3) Check DPM operation refer to the below table. Warm 6,500k °K X=0.318 (±0.03) Operating Condition Sync Video LED Wattage Y=0.334 (±0.03) (H/V) (SET) (W) Luminance Cool Min : 80 Typ : 110 Power S/W On Sleep mode - Off/Off Off Amber 1 (cd/m²) Inner pattern RGB,HDMI Medium Min : 80 Typ : 110 (204gray,80IRE) Warm Min : 80 Typ : 110 ■ HDMI2 DPM Operating condition with MHL HDMI2 Input MHL Cable HDMI & HDMI to DVI Cable * Total Assembly line should be check whether the color DPM X O coordinate(x,y) data refer to below table were meet or not. *Note : x ,y coordinates are drifted about 0.007 after 30 mins heat-run. So checking color coordinate within 5-min at 4.6. Model Name & SW Version & Adjust check. total assembly line, consider x,y coordinates might be * Press the ‘Instart’ key of ADJ remote controller up to 0.007 than x,y target of each color temperature. 4.6.1. Model Name& SW Version Check *Note : Manual W/B process using adjusts Remote control. 1) Check ‘Model Name’. 1) After enter Service Mode by pushing "ADJ" key, 2) Check ‘S/W Version’ (Refer to the IC Ver. in the BOM) 2) Enter "White Balance" by pushing "►" key at "White Bal- ance". 4.6.2. Adjust Check G 1) Check ‘Country Group’ WUG{––“Gv—›–•XG G G 2) Check ‘Area Option’ 3) Check ‘Tool Option’ (Refer to the BOM Comments) XUG{––“Gv—›–•YG G G YUG{––“Gv—›–•ZG G G ZUG{––“Gv—›–•[G G G 4) Check ‘Adjust ADC[Comp&RGB]’ is OK. [UG{––“Gv—›–•\G \UG{––“Gv—›–•]G G G 5) Check ‘EDID[RGB&HDMI1/2]’ is OK. ]UGj–œ•›™ Gn™–œ—G G G ~›ŒGiˆ“ˆ•ŠŒG * After check all, Press the 'EXIT' key of ADJ remote controller ^UGh™ŒˆGv—›–•G _UGhkjGjˆ“‰™ˆ›–•G G G G G G G G G G G j–“–™G{Œ”—UG yTnˆ•G ඔG G j––“G XWWG ඖG G to go out SVC menu. `UG~›ŒGiˆ“ˆ•ŠŒG G G G G G G G G G ඖG G G nTnˆ•G G XW[G G XWUGXWGw–•›G~iG G G G iTnˆ•G G X`YG G XXUG{Œš›Gwˆ››Œ™•G G G G G yTjœ›G G ][G G XYUGlkpkGkVsG G G G G G G G G G G G G G G G nTjœ›G G ][G G XZUGzœ‰GiVjG G G iTjœ›G G ][G G X[UG{–œŠGzŒ•š›› GzŒ››•ŽG {Œš›Twˆ››Œ™•G G vuG G X\GlŸ›UGp•—œ›Gh‹‘œš›G iˆŠ’“Ž›G G XWWG G G G G yŒšŒ›G G {–GzŒ›G G * When doing Adjustment, Please make circumstance as below. Copyright © LG Electronics. Inc. All right reserved. - 12 - LGE Internal Use Only Only for training and service purposes

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TROUBLE SHOOTING 1. No Power N Check Power connector N Check L800 All Replace Adapter Voltage Level (19V) OK ? Y Check IC809Output N Replace IC809 Voltage Level (3.3V_ST) Y N Replace IC802 & Check IC802 output Voltage Level (5V) Recheck Y Check IC806 Output N Replace IC806 & Voltage Level (1.15V) Recheck Y Check IC810 Output N Replace IC810 & Voltage Level (2.5V) Recheck Y Check IC807 Output N Replace IC807 & Voltage Level (1.5V) Recheck Y Check X201 Clock N Replace X201 24MHz Y Replace IC100 Flash Memory Copyright © LG Electronics. Inc. All right reserved. - 13 - LGE Internal Use Only Only for training and service purposes

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2. No Picture N Check WLED_ENABLE high N Check IC101 Module Back Light On ? R1127 Replace Main Scaler IC Y Y Check LED Driver output N Check LED Driver IC1100 (P1101/P1102 #1,2,5,6) Replace LED Driver IC Check Panel power N P1002(#1,2,3) 5V Replace IC807 IC807 Output 5V Y N Check IC101 Check Panel clock P601(#10,11,22,23) Repair Main B/D Y Check FFC Cable for damage N Replace Cable or open conductors. Y Replace T-con Board or module Copyright © LG Electronics. Inc. All right reserved. - 14 - LGE Internal Use Only Only for training and service purposes

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3. No Video Check RF Cable Y N 1. Check Tuner(TU3700 #5) Power (3.3V) Replace IC803 2. Check IC803 Output voltage(3.3V) Y N 1. Check Tuner(TU3700 #7) Power (1.8V) Replace IC805 2. Check IC805 Output voltage(1.8V) Y N Check Tuner(TU3700) I2C Signal Check IC101 SCL(R2609), SDA(R2610) Y N Check Tuner(TU3700) Replace Tuner(TU3700) Data, CLK, SYN, VAL Recheck Copyright © LG Electronics. Inc. All right reserved. - 15 - LGE Internal Use Only Only for training and service purposes

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4. No Video - Component Check input signal format Is it supported? Y Check Component Cable Wave form of Comp Y Wave form of Comp Pb Wave form of Comp Pr Y N Replace JK2800 or Check JK2800 Check Device Y Check signal N Replace R237,R239,R241 R237,R239,R241 C218,C220,C222 C218,C220,C222 Y IC101 has problem Wave form of C218 Wave form of C220 Wave form of C222 Copyright © LG Electronics. Inc. All right reserved. - 16 - LGE Internal Use Only Only for training and service purposes

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5. No Video - RGB Check input signal format Is it supported? Y Check RGB Cable Y N Replace JK400 or Check JK400 Check Device Y Check Hsync, Vsync N Replace R266, R267 R266, R267 Y Check signal RGB N Replace R228,R230,R232 R228,R230,R232 C204,C206,C208 C204,C206,C208 Y IC101 has problem Wave form of R4025(Vsync) Wave form of R4024(Hsync) Wave form of R228/C204 Wave form of R230/C206 Wave form of R232/C208 Copyright © LG Electronics. Inc. All right reserved. - 17 - LGE Internal Use Only Only for training and service purposes

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6. No Video - HDMI Check input signal format Is it supported? Y Check HDMI Cable for damage or open connector Y Check JK500/JK501 N Replace connector for proper connection or damage Y Check I2C Signal (JK500/JK501) N (#15, #16) Re download EDID data Y N Check HDCP Key (IC101) Replace Scaler(IC101) Copyright © LG Electronics. Inc. All right reserved. - 18 - LGE Internal Use Only Only for training and service purposes

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7. No Audio Make sure you can’t hear any audio and Device support the audio signal normally. Y Check Speaker and N its wire connection (P700) Replace connector or Speaker and the resistance Y 1.Check L800 Voltage Level (19V) N 2. Check Audio Amp(IC700) Power Replace IC809(3.3V) or Adapter (19V, 3.3V) Y Check Signal from IC700 N Replace IC700 L700,L701, L706, L709 Y Check Signal from IC101 N SDA/SCL Replace IC101 (R703/R214, R707/R213) Copyright © LG Electronics. Inc. All right reserved. - 19 - LGE Internal Use Only Only for training and service purposes

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BLOCK DIAGRAM Copyright © LG Electronics. Inc. All right reserved. - 20 - LGE Internal Use Only Only for training and service purposes

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EXPLODED VIEW IMPORTANT SAFETY NOTICE Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the Schematic Diagram and EXPLODED VIEW. It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent X-RADIATION, Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer. 921 910 900 920 535 400 LV1 A2 120 820 540 810 800 200 510 300 Copyright © LG Electronics. Inc. All right reserved. - 21 - LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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Copyright ⓒ 2013 LG Electronics. Inc. All right reserved. LGE Internal Use Only Only for training and service purposes

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