LCD TV SERVICE MANUAL CHASSIS : ML-024D MODEL : RZ-20LA70 CAUTION BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. Oct.,2003 P/NO : 3828VD0168C Printed in Korea...
No deviations are 6. Do not remove a replacement ES device from its protective package until allowed without prior approval by LG Electronics Inc. Service work should be immediately before you are ready to install it. (Most replacement ES devices...
DESCRIPTION OF CONTROLS All the functions can be controlled with the remote control handset. Some functions can also be adjusted with the buttons on the side panel of the set. Remote control handset MUTE POWER Before you use the remote control handset, please install the bat- teries.
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9. POWER switches the set on from standby or off to standby. 10. I/II selects the language during dual language broadcast. selects the sound output (option). 11. MENU MUTE POWER selects a me TV/AV I/II 12. PSM (Picture Status Memory) recalls your preferred picture setting.
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Side panel • RZ- 20LA70 series S-VIDEO VIDEO (MONO) AUDIO Back panel 1. ON/OFF (O/I) 7. POWER/STANDBY INDICATOR (O) switches the set on from standby or off to illuminates red in standby mode. standby. illuminates green when the set is switched on. Note : Power line lives even when the power is off.
ADJUSTMENT INSTRUCTION 1. Application Object This instruction is for the application to the LCD TV. 2. Notes (1) This set uses an adapter, so connect the adapter and the set correctly before adjustment. (2) The adjustment must be performed under the correct sequence.
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4. Option 1 data setting (200PR ~ A2 ST:1bit, SYS:2bit composition) OPTION OPTION TEXT I/II SV SCART A2 ST TEXT I/II SV SCART A2 ST 200PR 200PR Data Data - 8 -...
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OPTION OPTION TEXT I/II SV SCART A2 ST TEXT I/II SV SCART A2 ST 200PR 200PR Data Data - 9 -...
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OPTION OPTION TEXT I/II SV SCART A2 ST TEXT I/II SV SCART A2 ST 200PR 200PR Data Data - 10 -...
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OPTION TEXT I/II SV SCART A2 ST 200PR Data 5. Option2 data(ACMS~BBACK:1bit,LANG:3bit) OPTION OPTION ACMS BBACK LANG ACMS BBACK LANG Data Data - 11 -...
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6. Option3 data(IIC AFT~CH+AU:1bit) OPTION HiDEV IIC T MONO CH+AUS Data - 12 -...
TROUBLE SHOOTING 1. General Features Symptom Cause Check Point No screen Input error of inverter connector 1) Bend the pin legs of P802B connector -> recheck them 2) Check and repair IC805 SI4925. P1 and Pin 50 connector 1) Check and fix P1 connector being slipped out Cracked components and 1)Check and repair tuner board and main board...
REPLACEMENT PARTS LIST For Capacitor & Resistors, the CC, CX, CK, CN : Ceramic RD : Carbon Film charactors at 2nd and 3rd digit CQ : Polyestor RS : Metal Oxide Film in the P/No. means as follows; CE : Electrolytic RN : Metal Film RF : Fusible LOCA.
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For Capacitor & Resistors, the CC, CX, CK, CN : Ceramic RD : Carbon Film charactors at 2nd and 3rd digit CQ : Polyestor RS : Metal Oxide Film in the P/No. means as follows; CE : Electrolytic RN : Metal Film RF : Fusible LOCA.
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LCD TV SERVICE MANUAL CHASSIS : ML-041B MODEL : RZ-20LA70 (RZ-20LA70 Rev A) ) ID LABEL Model No. CAUTION BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. *Same looking with new chassis *Issue Date; 2004. 06...
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 X-RADIATION, Shock, Fire, or other Hazards.
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 This specification is applied to ML-041B chassis. 2. Requirement for Test Testing for standard of each part must be followed in below condition. (1) Temperature: 25°C ±...
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4. Feature and Function Item Specification Remark Teletext Top(option) TOP, FLOF REMOCON PAL/ NTSC NEC Code CVBS VIDEO Input Rear S-VIDEO Input Rear Component input Rear (option, NT) PERI TV Connector Rear (option,EU) Full SCART : 1 H/p input Rear RS-232 Discrete IR 2 Carrier Stereo...
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6.Engineering Specification Item Specification Remark Power Supply H/V Sync Video Power Consumption LED Color Normal On/On Active GREEN Stand By Off/On Suspend Mode On/Off DPM Off Mode Off/Off Cut-off Switch off PBP SWAP ON/OFF ITEM Spectification Remark D-SUB Pin Configuraion 1: RED 2: Green 3: Blue:...
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6-2.Power Item Unit Remark AC Power Shut Down Voltage DC Voltage, Inverter 22.8 25.2 DC Voltage, LCD Panel 11.4 12.6 DC Voltage, Audio 14.0 16.0 DC Voltage, Tuner(5) DC Voltage, Tuner(9) Japan only DC Voltage, Tuning(31) DC Voltage, VCTi(5) DC Voltage, VCTi(8) DC Voltage, VCTi(3.3) DC Voltage, VCTi(1.8) DC Voltage, GM2221 (3.3)
ADJUSTMENT INSTRUCTION 1. Application Object This instruction is for the application to the LCD TV. 2. Adjustment 2.1 Adjustment overview The unit is set to automatically adjust using the factory automation equipment. However when errors occur, it should be adjusted manually. 2.2 Auto Gain/Offset adjustment 2.2.1 RF Mode adjustment 2.2.1.1 Adjustment preparation...
SVC REMOCON To turn the TV on or off POWER To turn the TV on automatically if the power is supplied to the TV. (Use the POWER ON POWER key to deactivate): It should be deactivated when delivered. To activate the mute function. MUTE To check TV screen image easily.
TROUBLESHOOTING No power :[A]Process (LED indicator off) Check short of main B/D Check 15V or 5V or Change Lips Fail of Lips Pass Check Output of Change Q1100 Fail Q1100 Pass Check Output of Change IC1107, IC1104 IC1107, IC104 Fail Pass Change LED Assy Check LED Assy...
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No Raster :[B]Process Check LED Status Repeat A PROCESS on display unit Fail Check L900,L901 Change L900,L901, L902,L903 L902,L903 Fail Pass Check the input/ Change IC901 Output of IC901 Fail Pass Change inverter Check inverter connector or inverter Connector or inverter Fail Pass Change panel link...
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No Raster on Component signal Repeat [A] Process Pass Check the signal of Check JA1200 or L1200, L1202, L1203 RCA CABLE Fail Pass Re-soldering or Check the input/ Change the defect part, Fail output of IC1 Check X11 Re-soldering or Check the input/output Change the defect part Fail...
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No Raster on AV Signal No Raster on TV(RF) signal (Video, S-Video) Check 5V, 33V of TU1000 Repeat Check the output of Re-soldering or [A] Process Fail Fail TU1000 Change the defect part Pass Check the signal of Change L1209, L1210, L1209, L1210, L1212 L1212 Fail...
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No Sound Check the Change source input input source Fail Pass Re-soldering or Check the input/output Change the defect part of IC1 Fail Check X11 Pass Re-soldering or Check the input/output Change the defect part of IC100,IC101 Fail Pass Check the speaker Change speaker Fail Pass...
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BLOCK DIAGRAM DESCRIPTION 1. Video Controller Unit & Display Data Conversion Unit The video controller unit receives the video signals inputted through the tuner, AV port (AV1, AV2, S-Video, component), and converts them into an analog RGB signal through the microcomputer (VCTI) combined with the video decoder that integrates various functions in one chip.
METAL, PLATE 15, 20LA70 REAR A/V "B" T 4810V00925B BRACKET, REAR AV RZ-15LA70 ML024E HIPS . 5020V00871A BUTTON, CONTROL RZ-20LA70 ABS 8KEY . 3550V00383A COVER, REAR AV RZ-20LA70 HIPS 60HR . 4950V00157E METAL, HINGE ASSY NON 20LA70 4810V00767A BRACKET, STAND 20LA60 ML012B NON HINGE FRONT 4810V00768A...
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)