LG BP735 Service Manual

The LG BP735 is a Blu-ray Disc Player with 3D playback capability, built-in Wi-Fi, Smart TV features, USB connectivity, HDMI output, and support for various media formats. This service manual provides comprehensive information for technicians and service personnel including technical specifications, disassembly procedures, troubleshooting guides, and maintenance instructions.

1. Product Overview 2. Technical Specifications 3. Disassembly Procedures 4. Circuit Diagrams 5. Component Locations 6. Troubleshooting Guide 7. Test Procedures 8. Replacement Parts 9. Firmware Update 10. Safety Precautions 11. Service Contacts

Product Overview

The LG BP735 Blu-ray Disc Player features advanced video processing, network connectivity, and multimedia playback capabilities.

ComponentDescription
Main BoardCentral processing unit with HDMI controller
Power Supply BoardSwitching power supply unit
Optical DriveBlu-ray/DVD/CD laser assembly
Front Panel BoardDisplay and control buttons
Wi-Fi ModuleWireless network connectivity
USB PortsMedia playback and firmware update
HDMI OutputDigital audio/video output
Ethernet PortWired network connection
Audio OutputsDigital optical and analog audio
Remote SensorInfrared receiver for remote control

Technical Specifications

Disassembly Procedures

Follow these steps carefully for safe disassembly of the unit.

  1. Remove the top cover by unscrewing 4 screws on the bottom.
  2. Disconnect all cable connectors from the main board.
  3. Remove the front panel assembly by releasing plastic clips.
  4. Extract the optical drive unit by removing mounting screws.
  5. Separate the power supply board from the main chassis.

WARNING! Always disconnect power before disassembly. Use proper ESD protection.

Circuit Diagrams

Complete schematic diagrams for all major circuits.

Note: All voltages are DC unless specified otherwise.

Component Locations

Key component identification and board locations.

ComponentLocationPart Number
Main ICU1 on Main BoardRTD2985DQ
Memory ICU2 on Main BoardK4B2G1646E
Power RegulatorIC101 on PSUICE3B0565
Laser UnitOptical DriveKES-450AAA
Wi-Fi ModuleCN3 on Main BoardBCM4330

Troubleshooting Guide

SymptomPossible CauseCorrective Action
No PowerPower supply failureCheck fuse F101, measure +12V output
No Disc ReadingLaser assembly faultClean lens, check laser voltage, replace optical unit
No Video OutputHDMI circuit failureCheck HDMI IC U5, replace main board if necessary
Wi-Fi Not WorkingNetwork module failureReset network settings, check antenna connection
Disc Ejection IssuesMechanical mechanismCheck loading motor, replace drive mechanism

Test Procedures

Standard test procedures for verification and calibration.

  1. Power Supply Test: Measure +5V, +12V, +3.3V outputs
  2. Laser Power Test: Verify laser diode current
  3. Video Output Test: Check HDMI signal quality
  4. Audio Output Test: Verify digital and analog audio
  5. Network Test: Confirm Wi-Fi and Ethernet connectivity

CAUTION! Use proper test equipment and follow safety procedures.

Replacement Parts

Authorized replacement parts and ordering information.

Firmware Update

Procedures for firmware updates and recovery.

  1. Download latest firmware from LG support website
  2. Copy to USB drive in root directory
  3. Insert USB drive while player is off
  4. Press and hold PLAY button while powering on
  5. Follow on-screen update instructions

WARNING! Do not interrupt power during firmware update.

Safety Precautions

Important safety information for service personnel.

DANGER! High voltage present in power supply section.

Service Contacts

LG authorized service centers and technical support.

Note: This manual is for qualified service technicians only.

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