LG 50PA450C Service Manual

The LG 50PA450C is a 50-inch Plasma TV featuring HD resolution, built-in digital/analog tuner, multiple HDMI inputs, USB connectivity, component video inputs, AV composite inputs, headphone jack, remote control, energy saving modes, picture/audio adjustments, and smart energy features. Powered by 100-240V AC, 50/60Hz. Below are key sections for safety, technical specifications, installation, service procedures, troubleshooting, and maintenance.

1. Technical Specifications 2. Installation Guidelines 3. Service Safety Precautions 4. Circuit Diagrams 5. Disassembly Procedures 6. Component Locations 7. Troubleshooting Flowcharts 8. Test Points & Voltages 9. Parts List & Replacement 10. Firmware Update Procedures 11. Error Code Reference

Technical Specifications

Key components: Plasma display panel, power supply board, main logic board, Y-sustain board, X-sustain board, control board, and speaker system.

Specification	Details
Display Type	50-inch Plasma Panel
Resolution	1366 x 768 HD
TV System	ATSC/NTSC/QAM
Inputs	3x HDMI, 2x Component, 2x Composite, 1x RF
Outputs	Digital Audio Optical, Headphone Jack
Power Consumption	Typical 180W, Maximum 350W
Power Supply	100-240V AC, 50/60Hz
Standby Power	< 1W
Dimensions	With Stand: 1161 x 760 x 285 mm
Weight	With Stand: 23.5 kg

Installation Guidelines

Proper installation procedures for wall mounting and stand assembly.

Wall Mounting: Use VESA 400x400 compatible mount; ensure wall supports minimum 50kg.
Stand Assembly: Attach base to panel using provided screws; tighten securely.
Ventilation: Maintain minimum 10cm clearance around ventilation openings.
Power Connection: Use provided power cord; connect to grounded outlet.

WARNING! Plasma panel is fragile; handle with care. Use two people for installation.

Service Safety Precautions

Critical safety information for service technicians.

Disconnect Power: Always unplug from AC outlet before servicing.
High Voltage: Plasma sustain boards operate at dangerous voltages (>200V).
ESD Protection: Use anti-static wrist strap when handling circuit boards.
Capacitor Discharge: Wait 5 minutes after power disconnect for capacitor discharge.

DANGER! High voltage present even when unplugged. Qualified technicians only.

Circuit Diagrams

Power Supply: EAX64909601 - Main power circuit with standby and main voltages.
Main Board: EAX64909701 - Signal processing and input/output control.
Y-Sustain: EAX64909801 - Vertical scanning and address driver control.
X-Sustain: EAX64909901 - Horizontal sustain and energy recovery circuit.
Control Board: EAX64910001 - Front panel controls and IR receiver.
Logic Board: EAX64910101 - Timing controller and data processing.

Disassembly Procedures

Step-by-step disassembly instructions for component access.

Rear Cover Removal: Remove all screws from rear cover; carefully lift cover starting from bottom.

Board Access: Remove metal shielding; disconnect all cables from boards before removal.

Panel Separation: Remove bezel screws; carefully separate front bezel from panel assembly.

Component Locations

Main board (center), power supply (left), Y-sustain (top), X-sustain (bottom), control board (front right).

Power Supply Board: Left side rear - generates all operating voltages.
Main Board: Center rear - processes all input signals.
Y-Sustain Board: Top rear - controls vertical scanning.
X-Sustain Board: Bottom rear - controls horizontal sustain.
Control Board: Front right - buttons and IR receiver.

Note: Refer to component location diagram for exact positions.

Troubleshooting Flowcharts

Systematic approach to common service issues.

Symptom	First Check	Next Steps
No Power	Standby LED	Check power board voltages; replace fuse F101 if blown
No Picture/Sound	Backlight/audio	Test main board outputs; check sustain boards
Abnormal Colors	Input source	Check LVDS cable; test logic board; replace if needed
Image Retention	Usage patterns	Run pixel refresher; check Y-sustain board
Buzzing Sound	Sustain boards	Check sustain board components; replace if necessary

Test Points & Voltages

Critical test points and expected voltage readings.

VS Voltage: TP201 - 195V ±5V (main panel voltage)
VA Voltage: TP202 - 55V ±2V (address voltage)
VSC Voltage: TP203 - -190V ±10V (scan voltage)
5V Standby: TP101 - 5V ±0.2V (standby power)
12V Main: TP102 - 12V ±0.5V (main system power)
3.3V Logic: TP103 - 3.3V ±0.1V (logic board power)

Parts List & Replacement

Key replacement parts and ordering information.

Part Number	Description	Replaces
EAX64909601	Power Supply Board	Complete power assembly
EAX64909701	Main Board	Signal processing unit
EAX64909801	Y-Sustain Board	Vertical sustain circuit
EAX64909901	X-Sustain Board	Horizontal sustain circuit
6871Q-0593A	Plasma Panel	Complete display assembly

Firmware Update Procedures

Software update methods for service.

USB Update: Download firmware to USB drive; insert in service USB port.
Enter Service Menu: Press MENU button on remote 5 times quickly.
Select Update: Navigate to software update option; select USB source.
Wait Completion: Do not power off during update (approx. 5 minutes).

CAUTION! Incorrect firmware can damage set. Use only approved versions.

Error Code Reference

Error Code	Description	Solution
ER01	Main Board Communication Error	Check main board connections; replace if needed
ER02	Power Supply Fault	Check VS/VA voltages; replace power board
ER03	Y-Sustain Board Error	Test Y-sustain voltages; replace board
ER04	X-Sustain Board Error	Test X-sustain voltages; replace board
ER05	Temperature Sensor Fault	Check thermal sensors; replace main board

Reset Procedure: Unplug for 10 minutes; hold power button 30 seconds while unplugged.

Service Support: LG Service Center 1-800-243-0000; www.lg.com