LG 42PT250 Service Manual Download Page 40

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Making

Revision

PDP TV

Input

Block

Digital TV / HDMI Audio Problem

Follow procedure All source audio

trouble shooting

Check EDID Download

Re-download EDID data

◆

Digital TV

Check video output

Follow procedure All source audio

trouble shooting

Follow procedure digital TV

video trouble shooting

◆

HDMI

Check video output

Follow procedure HDMI video

trouble shooting

Repair Process-Reference data

A2-2

Only for training and service purposes

LGE Internal Use Only

Summary of Contents for 42PT250

Page 1: ...S READ THE SAFETY PRECAUTIONS IN THIS MANUAL CHASSIS PD13K MODEL 42PT250 42PT250 ZG North Latin America http aic lgservice com Europe Africa http eic lgservice com Asia Oceania http biz lgservice com Internal Use Only Printed in Korea P NO MFL67289503 1108 REV00 ...

Page 2: ...right 2011 LG Electronics Inc All rights reserved Only for training and service purposes CONTENTS CONTENTS 2 SAFETY PRECAUTIONS 3 SPECIFICATION 4 ADJUSTMENT INSTRUCTION 6 BLOCK DIAGRAM 13 EXPLODED VIEW 14 SCHEMATIC CIRCUIT DIAGRAM ...

Page 3: ...t s Neck 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 terminals phone jacks etc If the exposed met...

Page 4: ... 1 2D 42 HD No Item Specification Remark 1 Display Screen Device 106 cm 42 inch wide Color Display Module PDP 2 Aspect Ratio 16 9 3 PDP Module PDP42T3 RGB Closed Well Type Glass Filter 38 Pixel Format 1024 horiz By 768 ver 4 Operating Environment 1 Temp 0 deg 40 deg 2 Humidity 20 80 5 Storage Environment 3 Temp 20 deg 60 deg LGE SPEC 4 Humidity 10 90 6 Input Voltage AC 100 V 240 V 50 60 Hz Maker L...

Page 5: ... Portugal Romania Russia Serbia Slovenia Spain Sweden Slovakia Switzerland Turkey Ukraine UK 2 Broadcasting system 1 PAL SECAM BG EU PAL Market 2 PAL SECAM DK 3 PAL Ⅰ Ⅱ 4 SECAM L L 5 DVB T 6 DVB C 3 Receiving system Analog Upper Heterodyne Digital COFDM 4 Scart Jack 1EA PAL SECAM 5 Video Input 1EA PAL SECAM NTSC Side AV 6 Component Input 1EA Y Cb Cr Y Pb Pr 7 RGB Input RGB PC Analog D Sub 15Pin 8 ...

Page 6: ...HEAT RUN MODE 1 Press the POWER ON KEY on R C for adjustment 2 OSD display and screen display PATTERN MODE Set is activated HEAT run without signal generator in this mode Single color pattern WHITE of HEAT RUN MODE uses to check panel Caution If you turn on a still screen more than 20 minutes Especially digital pattern cross hatch pattern an after image may be occur in the black level part of the ...

Page 7: ...ushing ADJ key Enter Internal ADC mode by pushing G key at 5 ADC Calibration Caution Using power on button of the Adjustment R C power on TV ADC Calibration Protocol RS232 Adjust Sequence aa 00 00 Enter Adjust Mode xb 00 40 Component1 Input 480i ad 00 10 Adjust 480i Comp1 xb 00 60 RGB Input 1024 768 ad 00 10 Adjust 1024 768 RGB aa 00 90 End Adjust mode Required equipment Adjustment R C 6 Function ...

Page 8: ...Illumination is less than 10ux 2 Measure and adjust after sticking the Color Analyzer CA 100 CA210 to the side of the module 3 Aging time After aging start keep the Power on no suspension of power supply and heat run over 5 minutes O Auto adjustment Map RS 232C RS 232C COMMAND CMD ID DATA Wb 00 00 White Balance Start Wb 00 ff White Balance End Caution Color Temperature COOL Medium Warm One of R Ga...

Page 9: ...s y EDID have to be downloaded to Insert Process in advance 7 5 DDC EDID Write HDMI 256Byte Not used any more Use Auto D L 1 Connect HDMI Signal Cable to HDMI Jack 2 Write EDID DATA to EEPROM 24C02 by using DDC2B protocol 3 Check whether written EDID data is correct or not For SVC main Ass y EDID have to be downloaded to Insert Process in advance 7 6 EDID DATA 1 All Data HEXA Value 2 Changeable Da...

Page 10: ...e EYE Key on the adjustment remote controller 2 Check the Sensor DATA It must be under 10 and keep the data longer than 1 5s 3 Check OK Sensor DATA 0 4095 Power Saving Mode 0 12 IF you press IN STAP Button change Green Eye check OSD 9 Model name Serial number download 9 1 Model name Serial number D L 1 Press Power on key of service remocon Baud rate 115200 bps 2 Connect RS232 Signal Cable to RS 23...

Page 11: ...sible 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 5 Model Number D L like below photo 3 Input the Factory model name or Serial number like photo 4 Check the model name Instart menu Factory name displayed 5 Check the Diagnostics DTV country only Buyer model displayed 10 Download MAC Address CI Key and widevine Key Check w...

Page 12: ...ocket 2 Automatically detecting update file in USB Stick If your downloaded program version in USB Stick is Low it didn t work But your downloaded version is High USB data is automatically detecting 3 Show the message Copying files from memory 4 Updating is staring 5 0 Updating Completed The TV will restart automatically After turn on TV Please press IN STOP button on ADJ Remote control IF you don...

Page 14: ... 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 IMPORTANT SAFETY NOTICE A10 A9 LV1 A12 A21 A2...

Page 15: ...A 0 CI_ADDR 7 CI_DET CI_ADDR 8 PCM_A 1 CI_CD1 PCM_A 14 CI_CD2 CI_ADDR 5 CI_IOWR CI_DET CI_OE CI_TS_DATA 1 R113 100 EU BUF_FE_TS_CLK AR109 33 EU JK104 10067972 000LF EU EAG41860102 G1 G2 57 21 52 16 10 47 41 5 36 59 23 45 54 18 49 43 13 7 38 2 25 56 20 51 15 9 46 40 4 35 58 22 53 17 11 48 42 12 6 37 1 24 55 19 50 44 14 8 39 3 26 60 27 61 28 62 29 63 30 64 31 32 33 34 65 66 67 68 69 PCM_IOWR CI_TS_V...

Page 16: ...01 4A YL O SPRING 5A YL E LUG 3A YL CONTACT 4B WH O SPRING 3C RD CONTACT 4C RD O SPRING 5C RD E LUG C225 1000pF 50V R262 10K COMP2_R_IN C224 1000pF 50V 3 3V COMP2_L_IN R261 10K R259 470K COMP2_DET COMP2_Pb R265 12K COMP2_Pr R260 470K COMP2_Y R266 12K R264 10K COMP2_Y COMP2_Pb COMP2_Pr R286 0 R282 0 COMP2_Pr COMP2_Y COMP2_Y COMP2_Pb R284 0 R285 0 COMP2_Pr COMP2_Pb R283 0 R287 0 C228 10pF 50V READY ...

Page 17: ..._2_D R828 0 2D LVDS_DATA_2_A TE1P LVDS_DATA_1_C TB1N R800 0 2D TD1P R824 0 2D TA1N TC3P TC2N TD3N TA1N TC1N TC1P R815 0 2D PC_SER_CLK R833 0 2D TE2N TB1P TB2N R804 0 2D TE3P LVDS_DATA_1_E R812 0 2D R786 0 2D TE2P LVDS_DATA_1_C SDA_3 3V_MOD P_SCL R831 0 2D R830 0 2D LVDS_DATA_2_C R810 0 2D R822 0 2D TB1P LVDS_CLK_1 R789 0 2D TD2P UART_RXD TA2P PC_SER_DATA LVDS_DATA_2_D TCLK2N R785 0 2D 3 3V TCLK1P ...

Page 18: ... AE15 NC_33 AD2 NC_47 AD16 NC_46 AD15 NC_63 AE16 NC_66 AF3 NC_76 AF14 NC_32 AD1 NC_44 AD13 NC_61 AE14 NC_60 AE13 NC_51 AE4 NC_36 AD5 NC_67 AF4 NC_35 AD4 NC_49 AE2 NC_71 AF8 NC_40 AD9 NC_56 AE9 NC_72 AF9 NC_58 AE11 NC_69 AF6 NC_53 AE6 NC_74 AF11 NC_37 AD6 NC_43 AD12 NC_52 AE5 NC_75 AF12 NC_68 AF5 NC_59 AE12 NC_57 AE10 NC_70 AF7 NC_42 AD11 NC_38 AD7 NC_41 AD10 NC_54 AE7 NC_73 AF10 NC_39 AD8 NC_55 AE...

Page 19: ...SSQ_3 D1 VSSQ_4 D8 VSSQ_5 E2 VSSQ_6 E8 VSSQ_7 F9 VSSQ_8 G1 VSSQ_9 G9 B MDQSLB B MDQL3 B MDML B MA0 B MA7 B MWEB B TMA13 B MBA1 B TMA11 B MDMU B TMA5 B MCK B MA9 B MDQL6 B MDQSU B MDQSLB B MA1 B MBA0 B MDQU3 B MDQU5 B TMDQL0 B TMDQL1 B MA7 B TMDQU2 B MDQL5 B MDQL5 B MDQU7 B TMA2 B TMDQSLB B TMA3 B MDQL6 B TMDQSL B MDQSUB B MCKE B MCASB B MA12 B MWEB B TMBA0 B MDQU3 B MA11 B MA2 B MCKE B TMCKE B MDQ...

Page 20: ...63 10uF 16V READY C633 22uF 16V C632 22uF 16V R613 10K READY R638 10K READY C662 10uF 10V C607 47uF 6 3V C616 47uF 6 3V C659 47uF 6 3V IC606 AZ1085S 3 3TR E1 1 ADJ GND 2 OUTPUT 3 INPUT L709 BLM18PG121SN1D 3D 3 3V_3D C740 0 01uF 3D C746 10uF 10V 3D 1 8V C755 0 1uF 16V 3D C751 0 1uF 16V 3D C747 10uF 10V 3D L703 BLM18PG121SN1D 3D L710 BLM18PG121SN1D 3D C745 22uF 10V 3D 0 1uF C728 3D R775 330K 3D C739...

Page 21: ... TE4P B2 TE4N B1 TD4P B3 TD4N C3 TCLK4P C1 TCLK4N C2 TC4P D2 TC4N D1 TB4P D3 TB4N E3 TA4P E1 TA4N E2 TE3P F2 TE3N F1 TD3P F3 TD3N G3 TCLK3P G1 TCLK3N G2 TC3P H2 TC3N H1 TB3P H3 TB3N J3 TA3P J1 TA3N J2 TE2P K2 TE2N K1 TD2P K3 TD2N L3 TCLK2P L1 TCLK2N L2 TC2P M2 TC2N M1 TB2P M3 TB2N N3 TA2P N1 TA2N N2 TE1P P2 TE1N P1 TD1P P3 TD1N R3 TCLK1P R1 TCLK1N R2 TC1P T2 TC1N T1 TB1P T3 TB1N U3 TA1P U1 TA1N U2...

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Page 24: ...oken Freezing 4 5 Vertical bar Horizontal Bar 5 6 B Power Problem No Power Not turn on 6 7 Turn off Instant under watching 7 8 C Sound Problem No sound Sound distortion 8 10 E General function Problem RF emitter checking 10 First of all Check whether there is SVC Bulletin in GCSC System for these model Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE...

Page 25: ...tal X2 3 3V 5V Rom update 2 Replace Control B D A3 A5 A6 SVC R C Pattern Check Sound Sound OK Y Close Y Move No Picture No sound Section A2 Check LVDS Cable Replace Main B D Normal N Y N Move Power problem Section Normal Normal Move Power problem Section N A4 A8 A11 A12 A13 First of all Check whether all of cable between board was inserted properly or not Main B D Power B D Power B D Y sus B D Pow...

Page 26: ...mal Sound N Check Speaker ON Off setting in OSD Menu Close Y Normal Sound N Close Check Speaker jack connection Speaker Cable open Y Normal voltage N Check 17V Audio IC B on Power B D Check Power B D Replace Power B D Check Audio IC Short Replace Main B D SVC Bulletin Apply SVC Bulletin S W Upgrade etc N Normal Sound N Y Close Y Check Video A6 Copyright 2011 LG Electronics Inc All rights reserved ...

Page 27: ...Sus B D A5 Normal Picture Replace Y Sus B D Normal Picture Y N 1 Check Control B D 2 Replace Board Normal Picture A13 Check Y Drive B D Replace B D Y Close N Dark Picture Normal Picture Y Replace Module N Close 1 Check Z Sus Board 2 Replace Board A9 Check Picture mode setting Picture Noise Normal Picture Y N Close Y N Check RF Cable Connection Check Tuner Replace Normal Picture Close Close 3 A16 A...

Page 28: ...evel meter By using Diagnostics menu on OSD Menu Press red key on R C Signal TEST Signal strength Normal over 50 Signal Quality Normal over 50 Normal Picture Y N Normal Picture Y Close N N Check S W Version Booster menu On Off Check Off On Check S W Upgrade SVC Bulletin Check Tuner replace Main B D Normal Picture Y N Y Close Normal Picture Y Close N A6 1 2 Normal Picture N Contact with signal dist...

Page 29: ...liminate foreign material on Connector N A13 CTRL B D Control board Check connection of Connector COF TCP on CTRL B D X B D Check connection of Connector FFC on Y Drive B D A20 A20 1 Connector re connection 2 Eliminate foreign material on FFC 1 Check Y Drive B D 2 Replace Board A16 Normal Picture N Y Close Replace Module 1 Check CTRL B D 2 Replace Board Normal Picture N Y Close N Y Normal Horizont...

Page 30: ...heck Power cord was inserted properly N Normal Close Y Check ST BY 5V on Power Board Normal Voltage A22 N Normal Signal Y Check Power B D Replace Power B D Check AC DET Signal on Power B D A22 Check RL_ON Signal on Power B D N Normal Signal Y Check Main B D Replace Main B D Check the other pin s Output voltage on Power B D Normal Close Y N Replace Power B D A22 A22 A23 Copyright 2011 LG Electronic...

Page 31: ...Z Sus Board especially Short or Open 2 Replace defective B D A8 A11 To check Power B D Protection Check Power Off History RCU Off 7 Turn off Under watching Off Timer Set A24 Off timer Function off KEY Off 2HOUR Off NO Signal Off Y N Don t appear Power Off History Move No Power problem Section This is not problem Normal operation Copyright 2011 LG Electronics Inc All rights reserved Only for traini...

Page 32: ...heck Input signal Cable connection Cable open RF external HDMI SCART Normal Sound Y Close Check AVL off on Clear voiceⅡ off on Y Normal Sound N Close N Problem in all input Problem in only DTV Problem in external input SCART HDMI Check whether Problem happen in same output of other equipments or not By connecting same output cable of other equipment DVD Player Set Top Box different maker TV etc Y ...

Page 33: ...onnector solder Normal operating Check B 5V On Main B D A26 Normal Voltage Close N N Check 5V on Power B D Replace Power B D or Replace Main B D Power B D don t have problem A12 Check IR Output signal Normal Signal N Y Repair Replace IR B D N A26 Replace Main B D Y Y N Check local key Operation Normal operating Check Repair Cable connection Connector solder A26 A27 Check Key Output signal Y Normal...

Page 34: ...ck Repair Cable connection Connector solder A28 Replace RF emitter board Y Display normally Close N Normal operating N Replace Main B D Y A28 Check the signal between the RF emitter and Mani board Normal Signal Check the RF emitter SW Ver at SVC menu Normal operating Close Y N Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 35: ...A7 7 Y Sus Board Checking Method 50R3 A8 8 Z Sus Board Checking Method 50R3 A9 11 Check 5V on Power B D A12 12 Control Board Checking Method 50R3 A13 13 Mal discharge Symptom Picture A14 14 PDP Module Rom Ver Checking method A15 15 Y Drive B D Checking method A16 17 Half picture X B D Checking method 50R3 A18 Next page Continued PDP TV Repair Process Reference data Index Copyright 2011 LG Electron...

Page 36: ...ethod A21 21 Power Problem Check voltage on Power board A22 22 Power board Checking Method A23 23 Check Power off History A24 24 Sound Problem Speaker cable checking method A25 25 Check Remote control IR operation A26 27 Check RF emitter operation A28 PDP TV Repair Process Reference data Index Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal...

Page 37: ...r H Line Bar 5 In case of no picture you can judge defect cause Module or Main B D If patterns appear defect cause is Main B D Tilt Key Making Revision PDP TV Symptom A Picture Problem Check Module pattern by Tilt key Repair Process Reference data Item A1 A1 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 38: ...tion 1 Check Audio output by using oscilloscope GND R or R or L or L Audio output waveform 2 Check whether speaker jack was inserted properly or not Repair Process Reference data A2 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 39: ...R360 N Y Check IC700 Status PDN 23 Reset 31 is High Check Reset R380 PDN R374 They must be High 3 3V Y N Check IC303 Power 17V C340 3 3V R365 R374 Check 17V P600 1 2 3 3V IC606 2 Y N Y Check Mstar I2S Output 27 28 29 30 on IC303 Replace MSTAR IC400 N Replace AMP IC303 Y Repair Process Reference data A2 1 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes L...

Page 40: ...igital TV Check video output Follow procedure All source audio trouble shooting Follow procedure digital TV video trouble shooting Y N HDMI Y N Check video output Follow procedure HDMI video trouble shooting Y N Repair Process Reference data A2 2 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 41: ...ooting Y Follow procedure analog TV video trouble shooting N Replace MSTAR IC IC400 Check 3 on TU300 for 5V Check IC605 output Voltage N Y Check SIF signal C301 Replace TU300 N Y Check SIF signal C301 Check SIF line N Y Y Repair Process Reference data A2 3 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 42: ...02 Replace the Resistor Check IC400 signal JK210 Component C441 C442 JK100 JK101 SCART C435 C436 C437 C438 JK208 RGB C443 C444 JK207 Side AV C439 C440 Replace the Capacitor Follow procedure All source audio trouble shooting Making Revision PDP TV Input Block Component AV RGB Audio Problem Y Y Y N N N Repair Process Reference data A2 4 Copyright 2011 LG Electronics Inc All rights reserved Only for ...

Page 43: ...ical Audio Problem N Check Signal JK204 3 Check SPDIF signal R296 Replace MSTAR IC400 Check 5V 2 on JK204 Y N Check P601 Output L604 L605 Y A2 5 Repair Process Reference data Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 44: ...fer to the Module label for Va specification Check Vs Adjust Vs Voltage Refer to the Module label for Vs specification Repair Process Reference data A3 A3 Control Board Power Board Y Sus Board Z Sus Board PDP Module Label Main Board Check Vs Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 45: ... Code 128 Contains the manugacture No Manugacture No Adjusting Voltage DC Va Vs Adjusting Voltage Set up Vy Vsc Ve Vzb The trade name of LG Electronics Manufactured date Year Month Warning UL Approval Mark UL Approval No Model Name Max Watt Max Volts Max Amps Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 46: ...djustment 50R3 1 Vsc 150V on Y Sus B D Check Point R324 Adjustment Point VR301 2 Vy 190V on Y Sus B D Check Point R334 Adjustment Point VR302 A5 Module Label A5 Vy adjustment YSUS board Fuses Vsc adjustment Vzb Vy Vsc Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 47: ...ocess Reference data 3 VZB 115V on Z Sus B D Check Point R156 Adjustment Point VR204 Voltage Check Adjustment 50R3 Module Label A5 A5 ZSUS board Vzb Vy Vsc ZSUS board Vzb adjustment Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 48: ...IC600 Output 1 2V IC301 Output Y N Check Video color Check Monitor Out Video Scart out Check other input OSD Check IIC Line Check TU_SCL SDA Line N Replace Tuner N Y N Y Check Module N Y Change MSTAR IC400 Y A6 1 Repair Process Reference data A6 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 49: ...heck RF Cable Check CVBS signal TU601 11 Pin Replace Tuner TU300 Y N Check IC605 Output Voltage L610 Y N Y Replace MSTAR IC400 Check 5V voltage on TU300 Pin3 A6 2 Repair Process Reference data A6 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 50: ...al on R411 C413 C415 Y Check the damage of JK210 And Replace Connector N Y Replace MSTAR IC400 Y Check Component Cable Measured signals depend on the input signal A6 3 Repair Process Reference data Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 51: ...signal R404 R406 R408 Y Check P205 Replace connector P205 Y N Y Replace R404 R406 R408 N Replace MSTAR IC400 Y Check RGB Cable conductors for damage Y Measured signals depend on the input signal A6 4 Repair Process Reference data Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 52: ...423 CVBS Replace Capacitor Check AV port of JK207 Side JK100 JK101 Rear Replace connector N Replace MSTAR IC400 Check AV Cable for damage or open conductors Measured signals depend on the input signal Y Y Y Y N A6 5 Repair Process Reference data A6 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 53: ...ownload EDID Check HDMI Cable for damage or open conductors Replace Connector Replace MSTAR IC400 Y Y Y Y N N Check JK200 J201 J202 for proper connection or damage A6 6 Repair Process Reference data A6 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 54: ... If Fuse is defects it should check again voltage of 5V Va Va after replacing the fuse 3 In case there are no voltage of 5V Va Vs the board is failure it need to replace the board Pic 2 Pic 1 DMM mode A7 Pic 1 Fuse check Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 55: ... Measurement method 0 4V 0 5V Q610 Q612 0 45V 0 55V Q608 Q609 0 45V 0 55V Q601 Q602 0 35V 0 45V Q603 Q605 D604 D605 HS602 0 35V 0 45V Forward O L Overload Reverse D602 HS603 0 35V 0 45V Forward O L Overload Reverse Position Direction Circuit No HS601 D610 Q606 Q607 Forward 0 35V 0 45V 0 45V 0 55V Reverse O L Overload Specifications Diode FET HS603 HS601 HS602 YSUS board FS202 5V fuse FS203 Vs fuse...

Page 56: ...de FET by using digital multi meter Measuring Method Specifications 0 45V 0 55V Q102 Q103 0 5V 0 6V 0 35V 0 45V Q106 Q109 Position Direction Circuit No HS101 D114 D118 Q107 Q110 Forward 0 35V 0 45V 0 35V 0 45V Reverse O L Overload HS102 D109 D110 D108 D111 Q104 Q113 Q114 Forward 0 35V 0 45V Reverse O L Overload Diode FET ZSUS board FS202 5V fuse P203 HS102 HS101 Copyright 2011 LG Electronics Inc A...

Page 57: ...Check 5V 17V on Power B D Repair Process Reference data A12 Measure 5V voltage Power Board P813 P600 P813 Measure 17V voltage A12 17 02 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 58: ...heck crystal X1 output Check 3 3V 5V IC Check MCM at VS_DA by using digital multi meter Check Crystal X1 Check Input voltage Check IC IC53 IC51 Check oscillation of Crystal Normal 25 MHZ MCM Check point VS_DA GND Normal 3 3V Check MCM 3 3V Pin 14 15 18V IC51 IC53 P2 18V Pin14 15 5V 3 3V GND P105_FL1 FL2 5V Check LED On Copyright 2011 LG Electronics Inc All rights reserved Only for training and ser...

Page 59: ...e Symptom Repair Process Reference data Dark picture caused by Mal discharge A14 Dot type Mal discharge symptom Scan type Mal discharge symptom A14 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 60: ... Rom Label on control board Rom ver Label Check by using SVC Remote controller Press In start Press 0413 Select Panel Control Check Module Rom ver Refer to the Module Rom upgrade manual for Rom upgrade USB Type Jig A15 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 61: ...hod 50R1 Repair Process Reference data A16 Y drive board Check all output pins of scan IC connector using DMM Input signal connector Scan IC DMM Digital Multi Meter Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 62: ...RL board and X board Replace the X B D Check TCP connection after X B D replacement Connections between panel and X B D Right display Picture 1 Check replace right X B D Both ends display Picture 2 Check replace center X B D Left display Picture 3 Check replace left X B D Picture 1 Picture 2 Picture 3 Half display abnormal Partly display abnormal abnormal abnormal Va Va Va from CTRL from CTRL from...

Page 63: ...B D X B D 2 Check CTRL B D 3 Replace CTRL B D Many irregular vertical lines 1 Check connection CTRL B D X B D 2 Check CTRL B D 3 Replace CTRL B D Horizontal Line or Bar 1 Check connection Y Sus B D Panel 2 Check Y Sus B D 3 Replace Y Sus B D First of all Check whether all of cable between board was inserted properly or not Next Check whether there is foreign material on connector A19 Copyright 201...

Page 64: ...ck bad soldering on Chip resistance Defect symptom 192 Out Put TCP Type TCP Tape Carrier Package is film for IC connect with Electrode pattern Direct Bonding on X B D FFC Type Connector to connect between Electrode PAD Of PANEL and Y Drive B D Z Sus B D A20 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 65: ... Red Button on R C Æ Singal TEST Diagnostics 1 Check whether Signal Strength Signal Quality is over 50 or not 2 If Signal Strength Signal Quality is under 50 install the Booster to increase signal level A21 A21 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 66: ...blem Checking Order Checking Order Pin Map Power B D Main B D No Checking Point Spec Remark 1 STBY 5V 2 5V 5V 3 17V 17V 4 AC DET High 3 3V 5V 5 RL_ON High 3 3V 5V 6 M_ON High 3 3V 5V A22 P813 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 67: ...3 YUYANG If happen Power board Protection check whether there is Short or Open on Y SUS Z SUS B D or not Checking Method Va Voltage ADJ value value Adjust way Check 5V Va Vs voltage For Voltage specification refer to the PDP Module Label SC101 Vs Voltage ADJ Adjust Va Vs voltage Vs adjust Va adjust A23 P811 Power B D Y Sus B D P811 P813 NAME PIN 7 6 5 4 3 2 1 VS VS NC GND GND VA M5V Copyright 2011...

Page 68: ... Pop up Module Rom ver LAST HISTORY 1 5 Appear Power off history 5ea 1 is the latest history RCU OFF Power off by Remote control KEY OFF Mechanical power switch off 2HOUR OFF After turn on by OnTimer There is no operation for 2hours NO SIGNAL OFF In case that there is no signal for 15minutes A24 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Intern...

Page 69: ...r side or not 2 Check whether speaker cable have problem disconnection wire or not A25 Making Revision PDP TV Symptom Repair Process Reference data Speaker cable checking method C Sound Problem A25 Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Use Only ...

Page 70: ...lti meter when operate remote control Test Condition for case 3 Check Point Pin 1 IR TV power on status Multi meter Select DC 10V Checking method Check Remote control IR operation IR Local key Board for 2 3 4 550 TOOL IR Board A26 A26 TOUCH_VER_CHK NC NC IR GND KEY1 KEY2 LED RED GND SCL SDA GND 3 3V ST NC NC Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purpos...

Page 71: ...e 3 Check Point Pin 2 3 Key1 Key2 TV power on status Multi meter Select DC 10V A27 P P Vol Vol OK Menu Input Power D General function defect Check Local Key operation Symptom A27 TOUCH_VER_CHK NC NC IR GND KEY1 KEY2 LED RED GND SCL SDA GND 3 3V ST NC NC IR Local key Board for 2 3 4 550 TOOL Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal Us...

Page 72: ...ion for case 3 Check Point Pin 12 TV power on status Multi meter Select DC 10V A28 D General function defect Check RF emitter operation Symptom A28 3D_L R_SYNC 3D_RF_GPIO2 3 3V GND 3D_RF_RXD 3D_RF_TXD 3D_RFMODULE_RESET 3D_RFMODULE_DC 3D_RFMODULE_DD GND 3D_RF_GPIO0 3D_RF_GPIO1 RF emitter Board Copyright 2011 LG Electronics Inc All rights reserved Only for training and service purposes LGE Internal ...

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