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website:http://biz.LGservice.com LCD TV SERVICE MANUAL CHASSIS : LP78A MODEL : 26LC51(C) 26LC51(C)-ZA MODEL : 26LC7R 26LC7R-ZA CAUTION BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
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 Replacement Parts List. 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.
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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...
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IC Remove/Replacement Some chassis circuit boards have slotted holes (oblong) through Circuit Board Foil Repair which the IC leads are inserted and then bent flat against the Excessive heat applied to the copper foil of any printed circuit circuit foil. When holes are the slotted type, the following technique board will weaken the adhesive that bonds the foil to the circuit should be used to remove and replace the IC.
SPECIFICATION NOTE : Specifications and others are subject to change without notice for improvement. 1. Application range (4) Specification and performance of each parts are followed each drawing and specification by part number in This specification is applied to LP78A chassis. accordance with BOM.
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5. Model Specification(EU) Item Specification Remark Market Broadcasting system PAL BG/DK, PAL I/II, SECAM L/L’ Available Channel BAND VHF/UHF C1_C69 CATV S1_S47 Receiving system Upper Heterodyne SCART Input(2EA) PAL, SECAM, NTSC Full Scart 1EA, Harf 1EA Video Input (1EA) PAL, SECAM, NTSC Side AV S-Video Input (1EA) PAL, SECAM, NTSC...
*Use for Windows 95/98 : Setup_LptDrv_v0104_9x.exe This spec sheet is applied all of the 26/32/37/42” LCD *Use for Windows 2000/XP : Setup_LptDrv_v0202_XP_2000.exe TV(LP78A) by manufacturing LG TV Plant all over the world. *Use for Windows NT : Setup_LptDrv_v0104_NT.exe 2. Specification (3) Verification (Start >...
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3) Double click the blue box and confirm "Bootloader Version" as 42. 4) Click the "Erase Flash" button => Select the "Bootloader.bat" file(install > VCTP_download > Bootloader) => Push "OK" 5) Double click the download file low, then "edit" window will be opened =>...
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8) Click OK button at the "edit window". 4) Execute ‘Download.vi2c’ program in PC, then a main 9) Under Downloading process widow will be opened. 10) If download is failed, for example "No acknowledge from slave". Execute download again from(1). (2) Download method 2 (AV Plate Ass’y) 5) Double click the blue box and confirm "Bootloader Version"...
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9) Choose the Hex file in folder and execute downloading 2) Connect Zig to TV using a D-sub cable. with click "open button". 3) Execute ‘Download_CS.vi2c’ program in PC, then a 10) Click OK button at the "edit window" main widow will be opened. 4) Click "GO"...
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7) Double click the download file low then, "edit" window 12) If download is failed, for example "No acknowledge will be opened. from slave", execute download again from (1). 8) Chick the choice button I n the "edit window", then "file 4.3.
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(5) Push the Update NVM from File 5. EDID (The Extended Display Identification Data ) /DDC download (Display Data Channel) * Caution - Use the proper signal cable for EDID Download. - Never connect HDMI & D-SUB Cable at the same time. - Use the proper cables below for EDID Writing.
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=> Detail EDID Options are below(a, b, c, d, e) a. Product ID b. Serial No : Controlled on production line c. Month, Year : Controlled on production line <EDID DATA> ex) Montly: '03' => '03' Year: '2005' => '0F' d.
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(3) DDC adjustment support command set 6.4 Input the Shipping Option Data Adjustment CMD(HEX) 1) Push the ADJ key in a Adjust Remote control. Aging On/Off FF : ON / OO : OFF 2) Input the Option Number that was specified in the BOM, into the Shipping area.
TROUBLESHOOTING 1. No power (1) Symptom 1) Minute discharge does not occur at module. 2) Front LED does not activate. (2) Press check Start Check Is the power cord Plug in the power cord. plugged in? Are the line filter and Connect the cable.(SC100) PSU connected? Is the...
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2. Protect mode (1) Symptom 1) After lighting once it does not discharge minutely from the module. 2) The relay falls.(there is an audible “Click”.) 3) The color of the front LED turns from green to red. (2) Follow check Start Check Is the output the normal Low/High Is the Power Board...
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3. No Raster (1) Symptom 1) No OSD or image are displayed on the screen. 2) The front LED remains green. (2) Follow check Start Check Does Is output the normal Replace the Is the inverter minute discharge Low/High voltage except Power board.
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5. In the case of an unusual display in rear AV mode. Is video input of the A/V jack normal? Check the input source. (Check R172) Sam as Block A 6. In the case of an unusual display in Side AV mode. Is the video input of Check the input source.
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8. In the case of an unusual display in SCART 1 mode. Is the video input Check the input source. of the A/V jack normal? (Check R172) Sam as Block A 9. In the case of an unusual display in SCART 1_RGB mode. Is the video input of the A/V jack normal?(Check...
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11. In the case of an unusual display in component 1 mode. Is the video input of the A/V jack Check the input source. normal? (Check R248, R249,R250) Change the IC(IC500) 12. In the case of an unusual display in component 2 mode. Is the video input of the A/V Jk202 Check the input source.
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14. No Sound (1) Symptom 1) LED is green. 2) There is a picture but no sound. (2) Follow check Is there Set speaker on sound in any Is the speaker on? in the menu. mode? Is there Is the speaker Check the Speaker no sound only for Download the EDID data.
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15. HDMI mode Is only video Download EDID data each port. normal? 1. Check TV input mode. (HDMI 1 port support HDMI and DVI. So if you input DVI signal and PC audio from phone jack, You can hear PC audio.) Is only audio 2.
EXPLODED VIEW PARTS LIST PART NO. DESCRIPTION EAB30826701 Speaker,Full Range EN1527C-6603-1. ND 7W 8OHM 80DB 170HZ 71.5 X 42 X 29.5 EAJ36325401 LCD,Module-TFT V260B1 L03 WXGA 16/9 800:1 - CHI MEI OPTOELECTRONICS CORP MGJ32424603 Plate PRESS EGI T1.0 METAL HGI MGJ32424607 Plate PRESS H-GI T1.0 METAL HGI 26LC7D top bar ”A”...
REPLACEMENT PARTS LIST For Capacitor & Resistors, the CC, CX, CK, CN, CH : Ceramic RD : Carbon Film charactors at 2nd and 3rd digit in the CQ : Polyestor RS : Metal Oxide Film P/No. means as follows; CE : Electrolytic RN : Metal Film CF : Fixed Film RH : CHIP, Metal Glazed(Chip)