LG 42LB9R Service Manual free download

File name 42LB9R Service Manual.pdf

LCD TV SERVICE MANUAL CHASSIS : LP78A MODEL : 42LB9R 42LB9R-TD CAUTION BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. CONTENTS CONTENTS ... 2 SAFETY PRECAUTIONS ... 3 SPECIFICATION ... 6 ADJUSTMENT INSTRUCTION ... 9 TROUBLE SHOOTING ... 17 BLOCK DIAGRAM... 25 EXPLODED VIEW ... 26 REPLACEMENT PARTS LIST ... 28 SVC. SHEET ... -2- 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 Shock, Fire, or other Hazards. Do not modify the original design without permission of manufacturer. General Guidance Leakage Current Hot Check (See below Figure) Plug the AC cord directly into the AC outlet. An isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from the AC Do not use a line Isolation Transformer during this check. power line. Use a transformer of adequate power rating as this Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor protects the technician from accidents resulting in personal injury between a known good earth ground (Water Pipe, Conduit, etc.) from electrical shocks. and the exposed metallic parts. Measure the AC voltage across the resistor using AC voltmeter It will also protect the receiver and it's components from being with 1000 ohms/volt or more sensitivity. damaged by accidental shorts of the circuitry that may be Reverse plug the AC cord into the AC outlet and repeat AC voltage inadvertently introduced during the service operation. measurements for each ex