LG 42LH20R Page 1 Service Manual Download

Page: 1 / 28

LCD TV

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

CHASSIS : LP91A

MODEL : 42LH20R

42LH20R-MA

North/Latin America

http://aic.lgservice.com

Europe/Africa

http://eic.lgservice.com

Asia/Oceania

http://biz.lgservice.com

Internal Use Only

Summary of Contents for 42LH20R

Page 1: ... SERVICING THE CHASSIS READ THE SAFETY PRECAUTIONS IN THIS MANUAL CHASSIS LP91A MODEL 42LH20R 42LH20R MA North Latin America http aic lgservice com Europe Africa http eic lgservice com Asia Oceania http biz lgservice com Internal Use Only ...

Page 2: ...ght 2009 LG Electronics Inc All right reserved Only for training and service purposes 2 CONTENTS CONTENTS 2 PRODUCT SAFETY 3 SPECIFICATION 6 ADJUSTMENT INSTRUCTION 9 TROUBLE SHOOTING 14 BLOCK DIAGRAM 17 EXPLODED VIEW 18 SVC SHEET ...

Page 3: ...d 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 terminals phone jacks etc If the exposed metallic part has a return path...

Page 4: ... 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 charge...

Page 5: ...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 replac...

Page 6: ...e of each products is marked by models 4 Specification and performance of each parts are followed each drawing and specification by part number in accordance 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 No Item Specification Measureme...

Page 7: ...re mode Vivid 6 Component Video Input Y PB PR No Specification 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...

Page 8: ... 768 48 363 60 004 65 00 VESA XGA 4 1280 x 768 47 776 59 87 79 5 VESA WXGA 5 1360 x 768 47 72 59 799 84 62 VESA WXGA 6 1366 x 768 47 7 60 00 84 62 WXGA 7 1280 x 1024 63 595 60 00 108 875 SXGA 8 1920 x 1080 66 647 59 988 138 625 WUXGA 8 2 DTV Mode No Specification Remark Resolution H freq kHz V freq Hz Pixel Clock MHz 1 720 x 480 15 73 59 94 13 500 SDTV DVD 480I 525I Spec out 2 720 x 480 15 75 60 0...

Page 9: ...he MSTAR main software IC800 Mstar ISP Utility 1 Using D L Jig 2 Using USB Memory Stick 2 Input Tool Option Area option 3 Download the EDID EDID datas are automatically download when adjusting the Tool Option2 4 ADC Calibration RGB Component 4 Check SW Version 3 2 SET assembly adjustment items 1 Input Area option 2 Adjustment of White Balance Auto Manual 3 Input Tool Option Area option 4 Intellige...

Page 10: ... input menu can differ the model spec Refer to Job Expression of each main chassis ass y EBTxxxxxxxx for Option value Caution Don t Press IN STOP key after completing the function inspection 4 3 EDID D L method Recommend that don t connect HDMI and RGB D SUB cable when downloading the EDID If not possible recommend that connect the MSPG equipment There are two methods of downloading the edid data ...

Page 11: ...ress ENTER A 6 ADC adjustment is executed automatically 7 When ADC adjustment is finished this OSD appear 4 4 2 ADC Calibration RGB Using External pattern 1 Required Equipments Remote controller for adjustment MSPG 925F MSPG 1025 MSPG 3233 Pattern Generator 2 Process 1 Change the Input to RGB mode 2 Input the PC 1024x768 60Hz Horizontal Color Bar signal into RGB MSPG 925F Model 60 Pattern 65 3 Pre...

Page 12: ... Release the adjust mode after AC off on or std by off on in status of finishing the Hear run mode Release the Adjust mode when receiving the aging off command F3 00 00 from adjustment equipment Need to transmit the aging off command to TV set after finishing the adjustment Check DDC adjust mode release by exit key and release DDC adjust mode 3 Enter the adjust mode of white balance Enter the whit...

Page 13: ...easing the G 4 Standard color coordinate and temperature when using the CA100 or CA210 equipment To check the Coordinates of White Balance you have to measure at the below conditions Picture Mode User 1 Dynamic Contrast Off Dynamic Colour Off If you miss the upper condition the coordinates of W B can be lower than the spec 13 LGE Internal Use Only Copyright 2009 LG Electronics Inc All right reserv...

Page 14: ...ED Assy A PROCESS Fail Fail Pass Pass Check LEDAssy Change IC1002 Q1003 Pass Check short of IC1001 IC1003 IC1007 Fail Re soldering or Change defect part of IC1001 IC1003 IC1007 Fail No Raster B Process Check LED status On Display Unit Repeat A PROCESS Pass Fail Check Output of IC802 Change IC802 Fail Change Inverter Connector Or Inverter Fail Pass Fail Pass Change Module Fail Check LVDS Cable Pass...

Page 15: ...t part Pass No Raster on COMMPONENT Signal Check Input source Cable And Jack Pass Re soldering or Change the defect part Pass Check the Input Output Of IC800 Fail Re soldering or Change the defect part Repeat A B Process Check The Input Output Of JK101 Fail Pass No Raster on HDMI Signal Check Input source Cable And Jack Pass Check the Input Output Of JK301 JK302 JK303 Fail Re soldering or Change t...

Page 16: ...t Fail No Raster On AV Video S Video Signal No Signal On TV RF Signal Check Input source Cable And Jack Pass Check Input source Cable And Jack Pass Check The Input Output Of JK101 JK201 Pass Re soldering or Change the defect part Pass Fail Pass Repeat A B Process Check the Input Output Of IC800 Fail Re soldering or Change the defect part Pass Check The Input Output Of TU500 Pass Re soldering or Ch...

Page 17: ...DM 2_SCL SDA PC_SCL SDA MNT_VOUT AV2_VIN AV2_LIN RIN IIS_OUT USB USB_DN PN AUDIO AMP HDMI3_SCL SDA EEPROM 24C02 HDMI_DATA_3 TMDS TMDS TMDS HDMI3 USB Fo r D L EEPROM 256K Serial Flas h 8MByt e RGB_PC PC_Aud io TV RF COMP1 HDMI1 HDMI2 RS232 TX 232C Driver ST3232C PC_R G B HS VS PC_Aud io _L R 7 00m Vrms MNT_OUT 1Vp p SIDE_V 1Vp p SIDE_L SIDE_R 5 00mVrms DDR2 512MB EEPROM 24C02 Co mp 1_L R 5 00mVrms ...

Page 18: ...rical 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 manufacture...

Page 19: ...LUG2 3 0 SPRING 4 C LUG3 5 C LUG4 SHIELD 7 75 R102 0 HOTEL_OPT R103 0 HOTEL_OPT R105 0 NON_HOTEL_OPT R106 0 HOTEL_OPT R101 75 R109 75 R108 75 R107 220K R104 12K R118 12K R117 12K R119 12K R120 10K R113 10K R115 10K R116 220K R100 220K R111 220K R112 75 R110 75 R122 S VIDEO 75 R121 S VIDEO 10K R123 100pF READY C103 10K R114 PPJ226 01 JK100 9A GN 1P_CAN 4A GN O SPRING_A 3A GN CONTACT_A 9B BL 1P_CAN ...

Page 20: ...DDC_WP PC_HS PC_AUD_L 5V_MULTI DSUB_SCL PC_R CDS3C30GTH 30V D202 CDS3C30GTH 30V D203 ADUC30S03010L_AMODIODE 30V D200 ADUC30S03010L_AMODIODE 30V D201 30V D206 30V D205 ADUC30S03010L_AMODIODE 30V D204 ADUC30S03010L_AMODIODE 30V D209 30V D208 READY 30V D207 READY USB_DL_N USB_DL_P 0 REAR_USB R229 0 REAR_USB R230 USBDOWNSTREAM UB01123 4HHS 4F JK205 REAR_USB 1 2 3 4 5 0 1uF C203 0 1uF C200 0 1uF C201 0...

Page 21: ... DDC_WP THE SYMBOL MARK OF THIS SCHEMETIC DIAGRAM INCORPORATES SPECIAL FEATURES IMPORTANT FOR PROTECTION FROM X RADIATION 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 BSS83 CEC_READY Q303 S B D G CEC 3 3V_MST CEC_C CDS3C30GTH 30V CEC_READY D304 MMBD301LT1G 30V CEC_READY...

Page 22: ...420 4 7K R421 10K IR OUT R427 10K IR OUT R428 47K IR OUT R426 0 R417 NON_19_22_26 0 R400 READY 0 R403 NON_19_22_26 0 R413 READY 0 R402 8 B I T o r 5 2 s h a r p 4 7K 10BIT R401 4 7K JEIDA R407 0 R424 VESA 100 R409 READY 0 READY R405 0 OPC_ENABLE R412 470 R435 OPC_ENABLE SMAW200 03 P404 19_22_26 1 KEY1 2 KEY2 3 GND 120 ohm L404 120 ohm L407 NON_19_22_26 TF05 51S P401 1 2 3 4 5 6 7 8 9 10 11 12 13 1...

Page 23: ... 13 V OUT 5 RF_AGC 12 NC_4 11 MOPLL_AS 2 GND_1 19 NC_8 18 NC_7 10 SCL 4 NC_2 1 NC_1 17 NC_6 9 SDA 8 GND_2 3 B 5V 16 SIF OUT 7 NC_3 6 TP 3 3V_OPT 15 A OUT 21 SHIELD 20 NC_9 TAFT Z203D TU500 PAL_TUNER 14 NC_5 13 V OUT 5 RF_AGC 12 NC_4 11 MOPLL_AS 2 GND_1 19 NC_8 18 NC_7 10 SCL 4 NC_2 1 NC_1 17 NC_6 9 SDA 8 GND_2 3 B 5V 16 SIF OUT 7 NC_3 6 TP 3 3V_OPT 15 A OUT 21 SHIELD 20 NC_9 4 7K R502 220 R506 220...

Page 24: ... HOTEL_OPT Q602 E B C AMP_MUTE_HOTEL 3 3V_MULTI_MST SW_RESET 10uF 16V C600 10uF 16V C604 10uF 16V C609 3 3 R604 12 R608 12 R611 12 R610 12 R638 4 7K R663 4 7K R623 3 3 R626 3 3 R625 100 R601 3 3K R600 100 R676 100 R677 100 R678 100 R602 100 R603 0 R656 HOTEL_OPT 0 R673 12 R658 12 R653 12 R621 12 R654 4 7K R628 4 7K R667 3 3 R671 3 3 R635 1K R607 10K NON_HOTEL_OPT R613 12K HOTEL_OPT R613 5 6K R614 ...

Page 25: ...M 124 LVA1P 125 LVA1M 126 LVA0P 127 LVA0M 128 VDDP_2 129 LVB4P 130 LVB4M 131 LVB3P 132 LVB3M 133 LVBCKP 134 LVBCKM 135 LVB2P 136 LVB2M 137 LVB1P 138 LVB1M 139 LVB0P 140 LVB0M 141 AVDD_LPLL 142 GND_7 143 VDDC_4 144 GPIO150 I2C_OUT_MUTE 145 GPIO151 I2C_OUT_SD2 146 GPIO152 I2C_OUT_SD3 147 GND_8 148 GPIO51 149 GPIO52 150 GPIO53 151 GPIO54 152 GPIO55 153 GPIO56 154 GPIO57 155 GPIO58 156 VDDP_3 157 VDDC...

Page 26: ...CHEMETIC V_REF 0 1 u F 50V C918 HYB18TC512160B2F 2 5 IC900 J 2 VREF J 8 CK H2 VSSQ2 B7 UDQS N8 A4 P8 A8 L1 NC4 L2 BA0 R8 NC3 K7 RAS F8 VSSQ3 F3 LDM P3 A9 M3 A1 N3 A5 K8 CK R3 NC5 L3 BA1 J 7 VSSDL L7 CAS F2 VSSQ4 B3 UDM M2 A10 AP K2 CKE R7 NC6 M7 A2 N7 A6 M8 A0 J 1 VDDL K3 WE E8 LDQS P7 A11 K9 ODT A2 NC1 N2 A3 P2 A7 H8 VSSQ1 F7 LDQS A8 UDQS R2 A12 L8 CS E2 NC2 E7 VSSQ5 D8 VSSQ6 D2 VSSQ7 A7 VSSQ8 B8...

Page 27: ...AP2121N 3 3TRE1 IC1007 1 GND 2 VOUT 3 VIN 0 1 u F 16V C1014 BD9130EFJ E2 IC1001 3 ITH 2 VCC 4 GND 1 ADJ 5 PGND 6 SW 7 PVCC 8 EN 10K R1006 1 10W 2K 1 R1009 1 10W 3 3K 1 R1010 10uF 10V C1016 10uF 6 3V C1022 0 1 u F 50V C1015 0 1 u F 50V C1023 12K R1008 560pF 50V C1012 2200pF 50V C1055 READY 3 3 R1078 READY 10uF 16V C1004 10uF 16V C1013 10K R1079 AZ1085S 3 3TR E1 IC1003 1 ADJ GND 2 OUTPUT 3 INPUT 10u...

Page 28: ...Jan 2009 Printed in Korea P NO MFL60021513 ...

Search results

Summary of Contents for 42LH20R

Reviews:

Related manuals for 42LH20R

Brands by name

Popular brands

LG 42LH20R, Service Manual

Search results

Summary of Contents for 42LH20R

Reviews:

Related manuals for 42LH20R

Brands by name

Popular brands