LG Flatron L1918S Service Manual
  1. Manuals
  2. Brands
  3. LG Manuals
  4. Monitor
  5. L1918S
  6. Service manual

LG Flatron L1918S Service Manual

Color monitor
Hide thumbs Also See for Flatron L1918S:
Table of Contents

Advertisement

Quick Links

See also: User Manual
COLOR MONITOR
SERVICE MANUAL
MODEL:
LPL TLB2, A**SQP for HSD A01, A**RQP for HSD D10,
A**OQP for LPL TLL1 & TLL3)
CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
E-mail: http://www.LGEservice.com/techsup.html
L1918S
(L1918S-BNQ/SNQ.A**MQP for
**Sales Market
*To apply the MSTAR Chip.

Advertisement

Table of Contents
loading

Related Manuals for LG Flatron L1918S

Summary of Contents for LG Flatron L1918S

  • Page 1 E-mail: http://www.LGEservice.com/techsup.html COLOR MONITOR SERVICE MANUAL MODEL: L1918S (L1918S-BNQ/SNQ.A**MQP for LPL TLB2, A**SQP for HSD A01, A**RQP for HSD D10, A**OQP for LPL TLL1 & TLL3) **Sales Market CAUTION BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. *To apply the MSTAR Chip.

  • Page 2: Table Of Contents

    CONTENTS SPECIFICATIONS ........... 2 SERVICE OSD ............16 PRECAUTIONS ............3 TROUBLESHOOTING GUIDE ......17 TIMING CHART ............7 WIRING DIAGRAM ..........23 DISASSEMBLY ............8 EXPLODED VIEW...........24 BLOCK DIAGRAM...........11 REPLACEMENT PARTS LIST .......26 DISCRIPTION OF BLOCK DIAGRAM ....13 ADJUSTMENT ............15 SCHEMATIC DIAGRAM .........

  • Page 3: Precautions

    PRECAUTION WARNING WARNING FOR THE SAFETY-RELATED COMPONENT. BE CAREFUL ELECTRIC SHOCK ! • There are some special components used in LCD monitor that are important for safety. These parts are • If you want to replace with the new backlight (CCFL) or marked on the schematic diagram and the inverter circuit, must disconnect the AC adapter...

  • Page 4: Servicing Precautions

    SERVICING PRECAUTIONS CAUTION: Before servicing receivers covered by this 9. Use with this receiver only the test fixtures specified in service manual and its supplements and addenda, read this service manual. and follow the SAFETY PRECAUTIONS on page 3 of this CAUTION: Do not connect the test fixture ground strap publication.
  • Page 5 General Soldering Guidelines Replacement 1. Use a grounded-tip, low-wattage soldering iron and 1. Carefully insert the replacement IC in the circuit board. appropriate tip size and shape that will maintain tip 2. Carefully bend each IC lead against the circuit foil pad and solder it.
  • Page 6 Circuit Board Foil Repair At Other Connections Excessive heat applied to the copper foil of any printed Use the following technique to repair the defective copper circuit board will weaken the adhesive that bonds the foil pattern at connections other than IC Pins. This technique to the circuit board causing the foil to separate from or involves the installation of a jumper wire on the "lift-off"...

  • Page 7: Timing Chart

    TIMING CHART VIDEO SYNC Sync Front Blanking Total Video Sync MODE H / V Frequency Period Active Duration Porch Time Resolution Polarity Clock ( E ) Time ( A ) ( D ) ( C ) ( B ) H(Pixels) 25.175 31.469 640 x 350...

  • Page 8: Disassembly

    DISASSEMBLY-Set Hold the head & stand base and then twist Stand Push the hinge cover as arrow direction. until "Click”. After then pull down the stand. Disassemble the hinge cover as arrow direction. Remove the four screws. Disassemble the bezel from the bottom with a thin Disassembly Back Cover.
  • Page 9 Disassemble connector...
  • Page 10 DISASSEMBLY-Stand Pull the Base 2 ea Latches to inside until losing elasticity. Consequently, pull the stand body directly. Separate Stand Body & Stand Base. Fix Stand Base & Stand Body. Remove the three screws. Separate the hinge and stand.

  • Page 11: Block Diagram

    BLOCK DIAGRAM...
  • Page 12 BLOCK DIAGRAM-POWER Power EMI filter Rush Rectification Transformer Diode 100~240V prevention rectifier Starting resistor Switching Feedback 5V/12V circuit (PWM OVP protect control output OVP control IC & circuit circuit MOSFER) Inverter Transformer LC resonance Push-pull conversion circuit 4 CCFL lamps OVP circuit VDDA ON/OFF...

  • Page 13: Description Of Block Diagram

    DESCRIPTION OF BLOCK DIAGRAM 1. Video Controller Part. This part amplifies the level of video signal for the digital conversion and converts from the analog video signal to the digital video signal using a pixel clock. The pixel clock for each mode is generated by the PLL. The range of the pixel clock is from 25MHz to 135MHz.

  • Page 14: Lips Board Block Diagram

    LIPS Board Block Diagram Operation description_LIPS 1. EMI components. This part contains of EMI components to comply with global marketing EMI standards like FCC,VCCI CISPR, the circuit included a line-filter, across line capacitor and of course the primary protection fuse. 2.

  • Page 15: Adjustment

    ADJUSTMENT Windows EDID V1.0 User Manual 2. EDID Read & Write 1) Run WinEDID.exe Operating System: MS Windows 98, 2000, XP Port Setup: Windows 98 => Doesn’t need setup Windows 2000, XP => Need to Port Setup. This program is available for LCD Monitor only. 1.

  • Page 16: Service Osd

    SERVICE MODE 1) Turn off the power switch at the front side of the display. 2) Wait for about 5 seconds and press MENU, POWER switch with 1 second interval. 3) The SVC OSD menu contains additional menus that the User OSD menu as described below. a) CLEAR ETI: To initialize using time.

  • Page 17: Troubleshooting Guide

    TROUBLESHOOTING GUIDE 1. NO POWER No Power (Power Indicator Off) Check the Adapter/Inverter Please reinsert and section make sure the AC of 100-240 is normal Measure Q702 Check CN701 or replace Vout=1.8V U701 Q702, U701 PIN2=3.3V Check X401 oscillate Replace X401 waveforms are normal Replace U401...
  • Page 18 2. NO RASTER (OSD IS NOT DISPLAY)-LIPS No Raster (OSD Is Not Displayed) Check power board and find out a Check U701 short point as penning each power PIN 3 =5V? line Check U701 Check U701 Check C712 714 PIN 1 =3.3V? 1.
  • Page 19 2. NO RASTER (OSD IS NOT DISPLAY)-MSTAR No Raster (OSD Is Not Displayed) SCALER PIN96 1. Check C421 C423 97 OSCILLATES 2. Check X401 AS 14.318MHZ? 3. TROUBLE IN SCALER IC CHECK CONNECTION SCALER IC LINE FROM D-SUB TO PIN27 H SYNC ? SCALER PIN28 V SYNC? TROUBLE IN CABLE OR...
  • Page 20 4. TROUBLE IN DPM TROUBLE IN DPM SCALER IC PIN27 H SYNC ? CHECK H/V SYNC LINE PIN28 V SYNC? TROUBLE IN CABLE OR LCD MODULE...
  • Page 21 5. POWER No Power (Power Indicator Off) Check AC line Check AC line volt 110V or 220V Check F901, BD901 Check the voltage of C905(+) Check start voltage Check R906, R907, IC901 for the pin3 of IC901 The auxiliary voltage (IC901 pin 7) is Check D902,D902,C907 between 10V-16V...
  • Page 22 6. RASTER NO Raster (Lamp Off) Check C811 (+) Check power section =12V Check Interface section or Check ON/OFF main board signal Check Q801 Q802 Q803 CheckIC801 pin ZD801 2=5V? Check IC801 Check IC801 pin 5/pin6 Pin1/pin15 have the output of sawtooth wave at short time Replace IC801 Cut all the pin connector of...

  • Page 23: Wiring Diagram

    WIRING DIAGRAM 89G179J30H 8 or 89G179S30H 8 95G8014 6D643 95G8014 8D679 95G8014 3 28...

  • Page 24: Exploded View

    EXPLODED VIEW - 24 -...

  • Page 25: Exploded View Parts List

    EXPLODED VIEW PARTS LIST Ref. No. TPV part no. LGE part no. Description A34G0212ABNA1B ABJ33041502 Bezel (Front cabinet) Silver color A34G0212 B6A1B ABJ33041501 Bezel (Front cabinet) Black color A33G0135 1 1C MKC37803901 POWER LENS A33G0134-B6 1L MEY37805401 KEY BUTTON A15G0163-4 ADV33042601 MAIN FRAME for LPL TLB2 MAIN FRAME for LPL TLL1/3 ,...

  • Page 26: Replacement Parts List

    REPLACEMENT PARTS LIST DATE: 2006. 12. 21. LOC. PART NO. DESCRIPTION MAIN BOARD CAPACITORS C702 067G215Y479 7NV LOW ESR EC 4.7 UF 50V NC C702 067G215Y4797RV EC 105℃ CAP 4.7UF M 50V C717 067G305V100 3 10UF +-20% 16V C712 067G305V100 3 10UF +-20% 16V C710 067G305V100 3...
  • Page 27 C413 065G0603104 12 CER2 0603 X7R 16V 100N P C414 065G0603104 12 CER2 0603 X7R 16V 100N P C415 065G0603104 12 CER2 0603 X7R 16V 100N P C416 065G0603104 12 CER2 0603 X7R 16V 100N P C443 065G0603220 31 CER1 0603 NP0 50V 22P PM C442 065G0603220 31 CER1 0603 NP0 50V 22P PM...
  • Page 28 D403 093G 6433S DIODE BAV99 SEMTECH D404 093G 6433S DIODE BAV99 SEMTECH D405 093G 6433S DIODE BAV99 SEMTECH D702 093G 64S522SEM LL4148 D701 093G 64S522SEM LL4148 D414 093G 64S522SEM LL4148 D704 093G2004 2 SR24/PANJIT-SMT D704 093G2004 2A SM240A DO-214AC U401 056G 562105 TSUM16AL-LF U701...
  • Page 29 R414 061G0603101 RST CHIPR 100 OHM +-5% 1/10W R409 061G0603101 RST CHIPR 100 OHM +-5% 1/10W R486 061G0603102 RST CHIP 1K 1/10W 5% R477 061G0603102 RST CHIP 1K 1/10W 5% R476 061G0603102 RST CHIP 1K 1/10W 5% R475 061G0603102 RST CHIP 1K 1/10W 5% R474 061G0603102 RST CHIP 1K 1/10W 5%...
  • Page 30 R437 061G0603471 RST CHIPR 470 OHM +-5% 1/10W R451 061G0603472 RST CHIPR 4.7KOHM +-5% 1/10W R450 061G0603472 RST CHIPR 4.7KOHM +-5% 1/10W R725 061G0603472 RST CHIPR 4.7KOHM +-5% 1/10W R712 061G0603472 RST CHIPR 4.7KOHM +-5% 1/10W R705 061G0603472 RST CHIPR 4.7KOHM +-5% 1/10W R423 061G0603472 RST CHIPR 4.7KOHM +-5% 1/10W...
  • Page 31 C901 065G306M1022BP 1000PF Y1.CAP C900 065G306M1022BP 1000PF Y1.CAP C924 067G215V471 4H 470UF 25V C923 067G215V471 4H 470UF 25V C922 067G215V471 4H 470UF 25V C921 067G215V471 4H 470UF 25V C920 067G215V471 4H 470UF 25V C915 067G215V471 4H 470UF 25V C815 067G215V471 4H 470UF 25V C811 067G215V471 4H...
  • Page 32 C903 006G 31502 1.5MM RIVET 065G 2K152 1T C934 CERAMIC CAP 065G 2K152 1T C931 CERAMIC CAP 065G 2K152 1T C930 CERAMIC CAP 065G 2K152 1T C914 CERAMIC CAP 065G 2K152 1T C912 CERAMIC CAP C907 067G 5152207HT CAP 105℃ 22UF M 50V C907 067G215Y2207KT ED 105℃...
  • Page 33 D811 093G 64S511SEM IN4148W D905 093G 5212T52T DIODE 1N4007 DO-41 D901 093G 6026T52T RECTIFIER DIODE FR107 D902 093G 6038T52T FR103 D901 093G 6026W52T FR107 TRANSISTORs & Ics IC902 056G 139 3A PC123Y22FZOF IC901 056G 379 79 IC LD7522PS SOP-8 IC801 056G 608 10 0Z9938 IC903...
  • Page 34 R840 061G0805105 1MOHM 1/10W R839 061G0805105 1MOHM 1/10W R838 061G0805105 1MOHM 1/10W R820 061G0805105 1MOHM 1/10W R816 061G0805105 1MOHM 1/10W R813 061G0805105 1MOHM 1/10W R810 061G0805105 1MOHM 1/10W R913 061G0805114 RST CHIPR 110 KOHM +-5% 1/8W R908 061G0805202 RST CHIP 2K 1/8W 5% R924 061G0805240 1F 2.4KOHM 1/10W 1%...
  • Page 35 L904 073G 253 91 LS CHOKE BY LI SHIN L903 073G 253 91 LS CHOKE BY LI SHIN L901 073L 174 53 LG GP CHOKE L902 073L 174 55 LG GP LINE FILTER BY LITAI L902 073L 174 55LSG GP...
  • Page 36 L902 S73L17455VG TRANSFORMER ASS'Y L901 006G 31502 1.5MM RIVET L902 006G 31502 1.5MM RIVET F901 084G 33 10 FUSE CLIP F901 084G 41 3 3.15AH/250V FB901 071G 55 29 FERRITE BEAD...

  • Page 37: Schematic Diagram

    SCHEMATIC DIAGRAM 1. SCALER TSUM16AL SCHEMATIC XGA/SXGA LVDS OUTPUT VCC1.8 VCC3.3 GNDR GNDR GNDG GNDG VCC1.8 Vcc3.3 GNDB GNDB PC5V HSY NC HSY NC VSY NC VSY NC DDCA_SDA DDCA_SDA PC5V DDCA_SCL DDCA_SCL DET_VGA DET_VGA DDC_WP DDC_WP 3.INPUT A[0..9] A[0..9] A[0..9] VCC3.3 VCC5V...
  • Page 38 VCTRL R701 10KΩ 1/10W R702 CN701 51Ω 1/10W BL_ON R705 R706 0Ω 1/10W BL_ADJ 4.7KΩ 1/10W VCC1.8 C708 C702 +5V 3,4 Q701 R707 4.7uF Adj_BACKLIGHT 4 VCC1.8 D701 R708 10KΩ 1/10W LL4148 CONN C709 R710 Q702 R703 C710 PZT2907A 0.1uF 16V 10uF/16V C711 R711...
  • Page 39 CN405 RED+ FB410 30 OHM R434 56Ω 1/10W C432 0.047uF50V RED- GREEN+ FB411 30 OHM R435 56Ω 1/10W C433 0.047uF50V GREEN- BLUE+ FB412 30 OHM R436 56Ω 1/10W C434 0.047uF50V BLUE- PC5V R437 470Ω 1/10W C435 1000pF/50V PC5V R438 R439 R440 VGA_CON R441...
  • Page 40 VCC1.8 FB401 VDDC VDVI VMPLL AVDD VDDP VDDC VPLL FB402 VCC3.3 AVDD VCC3.3 FB404 VDVI VCC1.8 600 OHM VCC3.3 VCC3.3 C403 600 OHM 600 OHM 10uF/16V C407 C414 C415 C404 C405 C406 C402 0.1uF 16V 0.1uF 16V 0.1uF 16V VCTRL VCTRL LVA3P A[0..9]...
  • Page 41 VLCD CN102 A[0..9] A[0..9] LVA3P LVA3P LVA3P LVA3M LVA3M LVA3M LVACKP LVACKP LVACKM LVACKM LVA2P LVA2P LVA2M LVA2M LVA1P LVA1M LVA1P LVA0P LVA1M LVA0M LVA0P B[0..9] LVA0M B[0..9] LVB3P LVB3P LVB3M LVB3M LVBCKP LVBCKP LVBCKM LVBCKM LVB2P LVB2M LVB2P LVB1P LVB2M LVB1M LVB1P...
  • Page 42 2. INVERTER PT801 POWER X'FMR 80GL19T 8DN1 CN801 OPT1 C825 033G8021 2E U 10pF/3KV R836 +12V 65G 3J1006ET 1KΩ 1/8W 61G0805102 R805 C828 R802 470 1/4W 0.1uF 300KΩ 1/8W 61G1206471 65G0805104 32 61G0805304 R804 C811 10KΩ 1/8W 470uF/25V C813 R818 61G0805103 67G215L471 4H 1000pF...
  • Page 43 D901 FR107 D905 R904 93G 6026T52T ZD903 1N4007 150K 1/4W PTZ9.1B L902 93G 5212T52T 61G1206154 93G 39S 38 T 73G 174 55 LG GP 67G215L471 4H R929 C925 R909 L904 D906 3.3MΩ 1/4W 1.0uF/450V D903 D902 2.4Ω 1/4W 3.5uH SP10100...
  • Page 44 Jan. 2007 P/NO : MFL36713631 Printed in China...

Table of Contents