LG Electronics 20LS7D(C)-UB service manual

LCD TV

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE CHASSIS,

READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

CHASSIS : LA74E

MODEL : 20LS7D(C) 20LS7D(C)-UB

website:http://biz.LGservice.com

Contents

Main CONTENTS SAFETY PRECAUTIONS General Guidance AC Volt-meter Before returning the receiver to the customer, Leakage Current Cold Check(Antenna Cold Check) SERVICING PRECAUTIONS Page SPECIFICATION 4. General Specification(TV) 1. Application range 2. Specification 3. Test method 5. Chroma & Brightness 5.1. FOR 23LC7D (CONDITION : EZ-Picture "Daylight") 5.1. FOR 20LC7D (CONDITION : EZ-Picture "Daylight") 6. Component Video Input (Y, CB/PB, CR/PR) 8. Mechanical specification <20LC7D> <23LC7D> 7. RGB input (PC/DTV) ADJUSTMENT INSTRUCTION 1. Application Object 2. Notes 3. MICOM Download(Option) 3-1. Required Test Equipment 4. ADC-Set Adjustment 4-1. Synopsis 4-2. Test Equipment 4-3. Adjustment 5. EDID (The Extended Display Identification Data) / DDC (Display Data Channel) Download 5-1. HDMI EDID Data Input (1) Required Test Equipment (2) Preparation for Adjustments & Setting of Device 6-2. EDID DATA 7. Adjustment of White Balance 7-1. Required Equipment 7-2. Connection Diagram of Equipment for Measuring * RS-232C Command 7-3. Adjustment of White Balance(manual) TROUBLESHOOTING 1. TV/CATV doesn't display 2. Video doesn't display 3. Component doesn't display 4. RGB_PC doesn't display 5. HDMI doesn't display BLOCK DIAGRAM 6V KA7809A LCD Modu le Inverter(10Lamps) 74LVC14 TPS2052B THC63LVDM EXPLODED VIEW EXPLODED VIEW PARTS LIST No. PART NO. DESCRIPTION REPLACEMENT PARTS LIST CAPACITORs Page Page DIODEs ICs TRANSISTORs & FETs RESISTORs Page Page Page Page Page COILs & FILTERs & INDUCTORs CONNECTORs SWITCHes JACKs OTHERs ACCESSORY