LG OLED77C3 Series - User Manual

P/NO : MFL71991225 (2301-REV00)
CHASSIS : E*31C
MODEL : OLED77C3***
CAUTION
BEFORE SERVICING THE CHASSIS, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
OLED TV
SERVICE MANUAL
Copyright © 2023 LG Electronics Inc. All rights reserved. Only training and service purposes.
Any reproduction, duplication, distribution (including by way of email, facsimile or other electronic means),
publication, modification, copying or transmission of this Service Manual is STRICTLY PROHIBITED unless you
have obtained the prior written consent of the LG Electronics entity from which you received this Service Manual.
The material covered by this prohibition includes, without limitation, any text, graphics or logos in this Service
Manual.

LG OLED77C3 Series Specifications

General

Screen Size	77 inches
Display Technology	OLED
HDR	Dolby Vision, HDR10, HLG
Smart TV Platform	webOS
HDMI Ports	4
Audio Output	40W
Voice Assistant	Google Assistant, Amazon Alexa
Refresh Rate	120 Hz
Processor	α9 Gen6 AI Processor 4K
VRR	Yes
USB Ports	3
Resolution	3840 x 2160
Bluetooth	Yes
Wi-Fi	Yes

Summary

OLED TV SERVICE MANUAL

CAUTION

Important warning for users before servicing the chassis.

SAFETY PRECAUTIONS

IMPORTANT SAFETY NOTICE

Highlights safety-related parts and warnings for preventing hazards.

General Guidance

Provides general advice on using isolation transformers and handling components.

Leakage Current Hot Check

Details the procedure for measuring AC leakage current with the unit powered.

SERVICING PRECAUTIONS

General Servicing Precautions

Outlines basic safety rules and practices for servicing the TV.

Electrostatically Sensitive (ES) Devices

Explains how to handle sensitive electronic components to prevent static damage.

General Soldering Guidelines

Provides best practices for soldering electronic components and circuit boards.

SPECIFICATION

Application range

Defines the scope of application for the service manual's specifications.

Requirement for Test

Specifies the conditions and parameters for testing TV components and performance.

Test method

Outlines the testing methodologies and standards to be followed.

Model General Specification

Lists general specifications for various models and regions.

External Input Support Format

HDMI input(DTV)

Details the supported video formats for HDMI input in DTV mode.

HDMI Input (PC)

Lists the supported video formats for HDMI input when used with a PC.

SOFTWARE UPDATE

USB DOWNLOAD

Instructions for updating TV software using a USB drive.

NSU DOWNLOAD

Procedures for software updates via network connection.

BLOCK DIAGRAM

EXPLODED VIEW

WIRING DIAGRAM

ASSEMBLY; DISASSEMBLY GUIDE

Back Cover Disassembly Guide

Step-by-step instructions for removing the TV's back cover.

Back Cover Assembly Guide

Instructions for correctly reassembling the TV's back cover.

TROUBLE SHOOTING GUIDE

A. Video error

Troubleshooting steps for various video display problems.

B. Power error

Diagnostic procedures for issues related to power supply and TV on/off functions.

C. Audio error

Steps for resolving problems with the TV's sound output.

D. Function error

Troubleshooting common functional errors like remote control or Wi-Fi issues.

E. Noise

Guidelines for identifying and fixing audio or mechanical noise issues.

F. Exterior defect

Procedures for addressing physical damage or defects on the TV's exterior.

Guide to inspecting parts for symptoms of no power; no screen

A visual guide for checking power and screen related issues.

Appendix. How to check for OLED TV module defects