LG 42LG70 Series, Service Manual

Page 1: ...LCD TV SERVICE MANUAL CAUTION BEFORE SERVICING THE CHASSIS READ THE SAFETY PRECAUTIONS IN THIS MANUAL CHASSIS LA86A MODEL 42LG70 42LG70 UA website http biz LGservice com Internal Use Only ...

Page 2: ...c All right reserved Only for training and service purposes LGE Internal Use Only C 2008 CONTENTS CONTENTS 2 PRODUCT SAFETY 3 SPECIFICATION 6 ADJUSTMENT INSTRUCTION 12 TROUBLE SHOOTING 19 BLOCK DIAGRAM 30 EXPLODED VIEW 31 SVC SHEET ...

Page 3: ...afe to operate without damage of electrical shock Leakage Current Cold Check Antenna Cold Check With the instrument AC plug removed from AC source connect an electrical jumper across the two AC plug prongs Place the AC switch in the on position connect one lead of ohm meter to the AC plug prongs tied together and touch other ohm meter lead in turn to each exposed metallic parts such as antenna ter...

Page 4: ...ge on your body by touching a known earth ground 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 unit under test 2 After removing an electrical assembly equipped with ES devices place the assembly on a conductive surface such as aluminum foil to prevent electrostatic char...

Page 5: ...e 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 CAUTION Maintain original spacing between the repl...

Page 6: ...K520D3LZ1X 52LG70 9 Stand by 1W 10 Operating Environment 1 Temp 0 40 deg 2 Humidity 80 11 Storage Environment 1 Temp 20 60 deg 2 Humidity 85 1 Application Range This spec sheet is applied to the 42 47 52 LCD TV used LA86A chassis 2 Specification Each part is tested as below without special appointment 2 1 Temperature 25 5 C 77 9 F CST 40 5 C 2 2 Relative Humidity 65 10 2 3 Power Voltage Standard i...

Page 7: ...ightness uniformity 80 Full white 3 Color coordinate RED X Typ 0 640 Typ Y 0 330 GREEN X 0 280 Y 0 600 BLUE X 0 150 Y 0 060 WHITE X 0 272 Y 0 277 4 Contrast ratio 1200 1 1800 1 52LG70 900 1 1300 1 47LG70 1000 1 1400 1 42LG70 5 Color Temperature Cool 10 000 11 000 12 000 Test Signal Medium 8 300 9 300 10 300 HDMI input Warm 5 500 6 500 7 500 85 Full white pattern 6 Color Distortion DG 10 0 7 Color ...

Page 8: ...dition in video signal RGB signal Average Brightness measure specification 1 Impress 100 255Gray Level full white pattern at the same peak brightness measurement 2 Measure average brightness in 9 points Contrast ratio measure specification 1 Test display signal 30x30 dots White Window signal all Black Raster signal 2 Dark room measure condition Using touch type Color analyzer CA 100 Dark room in t...

Page 9: ...5 30 000 74 25 HDTV 1080P 14 1920 1080 33 71 29 97 74 176 HDTV 1080P 7 RGB PC No Resolution H freq kHz V freq Hz Pixel clock MHz Remark PC DDC 1 640 350 31 468 70 09 25 17 EGA X 2 720 400 31 469 70 08 28 32 DOS O 3 640 480 31 469 59 94 25 17 VESA VGA O 4 640 480 37 861 72 80 31 50 VESA VGA O 5 640 480 37 500 75 00 31 50 VESA VGA O 6 800 600 35 156 56 25 36 00 VESA SVGA O 7 800 600 37 879 60 31 40 ...

Page 10: ...6 70 06 75 00 VESA XGA O 12 1024 768 60 023 75 02 78 75 VESA XGA O 13 1280 768 47 776 59 870 79 5 CVT WXGA O 14 1360 768 47 712 60 015 85 50 VESA WXGA O 15 1280 1024 63 981 60 020 108 00 VESA SXGA O 16 1280 1024 79 976 75 025 135 VESA SXGA O 17 1600 1200 75 00 60 00 162 VESA UXGA O 18 1920 1080 67 5 60 148 5 HDTV 1080P O DTV 1 720 480 31 47 60 27 027 SDTV 480P 2 720 480 31 47 59 94 27 00 SDTV 480P...

Page 11: ...After Packing 1332 249 782 mm 2 Product Only SET 39 5 Kg With BOX 47 5 Kg 10 2 47LG70 No Item Content Unit Remark 1 Product Widt W Length D Height H mm Dimension Before Packing 1140 4 820 1 342 9 mm After Packing 1266 460 887 mm 2 Product Only SET 30 1 Kg With BOX 36 4 Kg 10 3 42LG70 No Item Content Unit Remark 1 Product Widt W Length D Height H mm Dimension Before Packing 1026 2 293 4 734 mm With...

Page 12: ...with white pattern 13Ch or Cross hatch pattern 09Ch then it can appear image stick near black level 3 Adjust ADC 3 1 Overview The ADC adjustment automatically sets the optimum black level and the gain and compensates the RGB deviation at the Analog to Digital converter 3 2 Devices and conditions to use 1 Jig RS 232C 2 MSPG925FA Series Pattern Generator MSPG925FA Resolution 480i comp1 MSPG 925FA mo...

Page 13: ...justment mode If the 7 adjustment is ended press the ADJ or the Exit of the adjustment R C to exit from the adjustment mode 4 EDID The Extended Display Identification Data DDC Display Data Channel download 4 1 Overview VESA specification Function to implement the Plug and Play for automatically reconfiguring the user Øs environment to directly use by exchanging the information with no direct comma...

Page 14: ...FF 00 1E 6D 01 00 01 01 01 01 10 00 11 01 03 80 73 41 96 0A CF 74 A3 57 4C B0 23 20 09 48 4C AF CF 00 31 40 45 40 61 40 81 80 A9 40 30 01 01 01 01 01 01 02 3A 80 18 71 38 2D 40 58 2C 40 45 00 C4 8E 21 00 00 1E 66 21 50 B0 51 00 1B 30 50 40 70 36 00 C4 8E 21 00 00 1E 00 00 00 FD 00 30 60 58 1F 64 11 00 0A 20 20 20 20 20 20 00 00 00 FC 70 00 4C 47 20 54 56 0A 20 20 20 20 20 20 20 01 8A 0 1 2 3 4 5 6...

Page 15: ... The adjustment condition should be set by the Power On key 2 Press the ADJ of the R C to enter into EZ ADJUST 3 Select 10 TEST PATTERN with the CH key and press the Enter key for 30 minutes or longer to perform the heat run 4 Perform the zero calibration of the Color Analyzer and fix the sensor with the 10cm or less distance at the center of the LCD module surface when adjusting 5 Press the ADJ o...

Page 16: ...ted into the set When it is disconnected or loosened test after inserting it 2 Perform the automatic test on the GND resisting pressure The set with power cord the cord and the A V completely inserted into the tuner is loaded on the pallet and entered into the automatic test process Connect the D terminal AV JACK tester Turn on the automatic GWS103 4 Perform the GND TEST When the result is NG the ...

Page 17: ...16GMF IC4015 Power supply 5V P4004 Pin 3 SCL D sub Pin 10 SDA D sub Pin 7 10 5 How to adjust for downloading 1 fter executing LGE Monitor Tools v1 1 click the first icon See the figure 2 When the screen is displayed as shown at the below figure set the items as follows MCU Select MTV512M64 R W Option Auto Write Verify Jig Option Myson Transmit Speed Medium Check blank PORT Select the Parallel Port...

Page 18: ...d into the USB jack on the main board the following screen example is displayed after several seconds 3 Check the current version at Current TV Software Version Information check the S W version to upgrade at New Found TV Software Version Information and press the Enter button of the TV remote controller 4 Downloading is proceeded as shown at the below screen and when it is ended turning on off is...

Page 19: ... 19 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 TROUBLESHOOTING ...

Page 20: ... 20 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 21: ... 21 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 22: ... 22 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 23: ... 23 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 24: ... 24 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 25: ... 25 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 26: ... 26 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 27: ... 27 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 28: ... 28 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 29: ... 29 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 ...

Page 30: ... 30 Copyright LG Electronics Inc All right reserved Only for training and service purposes LGE Internal Use Only C 2008 BLOCK DIAGRAM ...

Page 31: ...00 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 o...

Page 32: ......

Page 33: ......

Page 34: ......

Page 35: ...Feb 2008 Printed in Korea P NO MFL42112404 ...