The LG 50PC1D is a 50-inch Plasma TV featuring high-definition resolution, built-in digital/analog tuner, multiple input connections including HDMI, component video, composite video, S-Video, PC input, and USB port. This service manual provides detailed technical information for qualified service technicians including safety precautions, disassembly procedures, troubleshooting guides, circuit diagrams, and replacement parts information.
Important safety information for service technicians working on the LG 50PC1D Plasma TV.
| Warning | Description |
|---|---|
| High Voltage | Plasma panel operates at lethal voltages up to 400V AC |
| Power Supply | Main power supply contains hazardous voltages even when unplugged |
| ESD Protection | Always use anti-static wrist strap when handling circuit boards |
| Panel Handling | Plasma panel is fragile and heavy - handle with extreme care |
| Capacitor Discharge | Allow 5 minutes for power supply capacitors to discharge after disconnecting power |
| X-Ray Radiation | No user serviceable parts inside - certified technicians only |
| Heat Sinks | Some components remain hot after power off - allow cooling time |
| Tools Required | Use insulated tools and test equipment rated for high voltage |
Detailed technical specifications for the LG 50PC1D Plasma TV.
Step-by-step instructions for disassembling the LG 50PC1D Plasma TV.
WARNING! Always disconnect power and discharge capacitors before disassembly. Handle plasma panel with extreme care to avoid permanent damage.
Complete circuit diagrams for all major components and subsystems.
| Diagram | Description | Page Reference |
|---|---|---|
| Power Supply | Main power supply circuit (PWM control, rectification, filtering) | Page 25-28 |
| Main Board | Digital signal processing and input switching | Page 29-35 |
| Y-Sustain | Y-sustain board circuit for panel addressing | Page 36-38 |
| X-Sustain | X-sustain board circuit for panel sustain | Page 39-41 |
| Logic Control | Timing controller and data processing | Page 42-44 |
| Audio Board | Audio amplification and processing circuits | Page 45-47 |
| Buffer Boards | Upper and lower buffer board circuits | Page 48-50 |
Printed circuit board layouts with component identification and test points.
Note: All layouts include component values, test point voltages, and critical measurement points.
Reference waveforms and voltage measurements for troubleshooting.
Measurement Conditions: All measurements taken with 10:1 probe, 20MHz bandwidth limit, ground reference to chassis.
Systematic troubleshooting procedures for common failure modes.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| No Power | Power supply failure, fuse blown, standby circuit | Check AC input, fuses F101/F102, measure standby 5V |
| No Picture/Sound OK | Sustain boards, buffer boards, logic control | Check Vs, Va voltages, verify sustain waveforms |
| Sound No Picture | Y-sustain, X-sustain, panel drive | Measure sustain board outputs, check buffer boards |
| Intermittent Shutdown | Overcurrent protection, thermal shutdown | Check current sense circuits, heat sink temperatures |
| Vertical Lines | Buffer board failure, panel connection | Replace affected buffer board, check flex cable connections |
| Color Problems | Main board video processing, cable connections | Check video input signals, main board RGB processing |
| No Audio | Audio board, speakers, main board audio | Check audio board power, speaker connections, input signals |
Factory adjustment procedures using service remote and service mode.
CAUTION! Record original settings before making adjustments. Incorrect settings may cause permanent damage.
Complete list of replacement parts with manufacturer part numbers.
| Part Number | Description | Qty |
|---|---|---|
| EAY40506101 | Main Board Assembly | 1 |
| EAY40506201 | Power Supply Board | 1 |
| EAY40506301 | Y-Sustain Board | 1 |
| EAY40506401 | X-Sustain Board | 1 |
| EAY40506501 | Upper Buffer Board | 1 |
| EAY40506601 | Lower Buffer Board | 1 |
| EAY40506701 | Logic Control Board | 1 |
| 6871Q2H011A | Plasma Panel 50" | 1 |
| 3945N00107A | Front Bezel Assembly | 1 |
| 3945N00108A | Rear Cover Assembly | 1 |
Detailed exploded views showing assembly relationships and screw locations.
Note: All views include reference numbers matching parts list for easy identification.
Procedures for accessing and navigating service mode menus.
WARNING! Service mode contains critical settings. Incorrect adjustments may render TV inoperable. Only qualified technicians should access service mode.