Lg376000

Internal Use Only
website:http://biz.LGservice.com

LCD TV SERVICE MANUAL
CHASSIS : LD89D

MODEL : 37LG6000
CAUTION

37LG6000-ZA

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

CONTENTS

CONTENTS .............................................................................................. 2 PRODUCT SAFETY..................................................................................3 SPECIFICATION ........................................................................................6 ADJUSTMENT INSTRUCTION ...............................................................15 TROUBLE SHOOTING ............................................................................17 BLOCKDIAGRAM...................................................................................24 EXPLODED VIEW .................................................................................. 25 SVC. SHEET ...............................................................................................

Copyright C 2008 LG Electronics. Inc. All right reserved. Only for training and service purposes

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LGE Internal Use Only

SAFETY PRECAUTIONS
IMPORTANTSAFETY 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 Shock, Fire, or other Hazards. Do not modify the original design withoutpermission of manufacturer.

General Guidance
An isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC power line. Use a transformer of adequate power rating as this protects the technician from accidents resulting in personal injury from electrical shocks. It will also protect the receiver and it's components from being damagedby accidental shorts of the circuitry that may be inadvertently introduced during the service operation. If any fuse (or Fusible Resistor) in this TV receiver is blown, replace it with the specified. When replacing a high wattage resistor (Oxide Metal Film Resistor, over 1W), keep the resistor 10mm away from PCB. Keep wires away from high voltage or high temperature parts.

Leakage Current HotCheck (See below Figure) Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check. Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor between a known good earth ground (Water Pipe, Conduit, etc.) and the exposed metallic parts. Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/volt or more sensitivity. Reverseplug the AC cord into the AC outlet and repeat AC voltage measurements for each exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS which is corresponds to 0.5mA. In case any measurement is out of the limits specified, there is possibility of shock hazard and the set must be checked and repaired before it is returned to the customer.

Leakage Current Hot Check circuitBefore returning the receiver to the customer,
always perform an AC leakage current check on the exposed metallic parts of the cabinet, such as antennas, terminals, etc., to be sure the set is safe to operate without damage of electrical shock.

AC Volt-meter

Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source, connect an electrical jumper acrossthe 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 to the chassis, the measured resistance should be between 1MΩ and 5.2MΩ. When the exposed metal has no...