1. Introduction
This manual provides essential information for the safe and effective installation, operation, and maintenance of the L4L105 TV Power Supply Board. This board is designed as a replacement or repair component for compatible television sets, ensuring stable power delivery to various internal components. Please read this manual thoroughly before attempting any installation or repair work.
2. Safety Information
- Electrical Hazard: This product operates with high voltage. Installation and repair should only be performed by qualified technicians. Disconnect the TV from the main power supply before handling the power board.
- Capacitor Discharge: Power supply boards contain large capacitors that can store dangerous electrical charges even after being disconnected from power. Allow sufficient time for capacitors to discharge or safely discharge them before touching any components.
- Fuse Replacement: For continued protection against the risk of fire, replace fuses only with the same type and rating as specified on the board.
- Static Electricity: Use anti-static precautions (e.g., anti-static wrist strap) when handling the board to prevent damage to sensitive electronic components.
- Physical Damage: Avoid bending, dropping, or applying excessive force to the board, as this can cause irreparable damage.
3. Product Overview
The L4L105 Power Supply Board is a critical component responsible for converting AC power from the wall outlet into the various DC voltages required by a television's internal circuits. It typically features distinct "HOT" and "COLD" sections, separated by an isolation barrier, to ensure user safety and proper operation.
Key Areas:
- Input Section (HOT side): Receives AC power, typically includes rectifiers, filters, and primary switching components.
- Output Section (COLD side): Delivers regulated DC voltages to the TV's main board, backlight inverter, and other modules.
- Connectors: Various connectors for AC input, DC outputs, control signals, and ground.
4. Specifications
| Feature | Detail |
|---|---|
| Model | L4L105 (Variants: 168P-5835-L4L105-00, 168P-5835-L4L105-01) |
| Product Type | TV Power Supply Board / Power Card / Power Support Board |
| Input Voltage | 100-240V~ AC, 50/60Hz |
| Output Voltage 1 | +12V DC, 3A |
| Output Voltage 2 | 85V DC, 350mA (2 Channels) |
| Origin | Mainland China |
| Certifications | CE, FCC, RoHS, UL (where applicable) |
| Compatible Equipment | Display Equipment (TVs) |
5. Installation / Setup
Disclaimer: Installation of this power supply board requires technical expertise and should only be performed by qualified personnel. Improper installation can lead to electric shock, fire, or damage to the television.
- Preparation:
- Ensure the television is completely disconnected from the power outlet.
- Place the TV on a soft, clean surface to prevent scratching the screen.
- Gather necessary tools: screwdrivers, anti-static wrist strap, multimeter (optional, for testing).
- Accessing the Old Board:
- Remove the back cover of the television. Note the location and type of all screws.
- Locate the existing power supply board. It is typically the largest board connected directly to the AC input.
- Removing the Old Board:
- Carefully disconnect all cables connected to the old power supply board. Take photos or make notes of cable orientations and connections for reassembly.
- Unscrew the old power supply board from the TV chassis.
- Gently lift and remove the old board.
- Installing the New Board:
- Align the new L4L105 power supply board with the mounting holes in the TV chassis.
- Secure the board with the appropriate screws. Do not overtighten.
- Reconnect all cables to the new board, ensuring they are seated firmly and correctly according to your notes or photos. Pay close attention to the input and output connectors.
- Testing (Before Closing):
- Before replacing the back cover, temporarily connect the TV to power.
- Observe if the TV powers on and functions correctly (e.g., backlight, display).
- If issues arise, immediately disconnect power and re-check all connections.
- Final Assembly:
- Once confirmed operational, disconnect power again.
- Replace the TV's back cover and secure all screws.
6. Operation
The L4L105 Power Supply Board operates automatically once installed correctly and connected to the television's main board and AC power. Its function is to provide stable and regulated power to the TV's components. There are no user-adjustable settings on the power supply board itself.
Ensure the TV is connected to a stable power source within the specified input voltage range (100-240V AC).
7. Maintenance
The L4L105 Power Supply Board is designed for long-term, maintenance-free operation. However, to ensure its longevity and the overall health of your television:
- Keep Clean: Periodically, with the TV unplugged, gently clean any dust accumulation on the board using compressed air or a soft brush. Dust can act as an insulator, leading to overheating.
- Ventilation: Ensure the TV's ventilation openings are not blocked to allow for proper heat dissipation from internal components, including the power supply.
- Avoid Spills: Prevent liquids from coming into contact with the television, as this can cause short circuits and damage to the power board.
8. Troubleshooting
If your TV experiences issues after installing the L4L105 power supply board, consider the following common troubleshooting steps:
- No Power / TV Dead:
- Check if the TV is properly plugged into a working power outlet.
- Verify all cable connections to the power board are secure.
- Inspect fuses on the power board for continuity (requires a multimeter and technical knowledge).
- Intermittent Power / Flickering:
- Ensure all connectors are firmly seated. Loose connections can cause intermittent issues.
- Check for any visible signs of damage or bulging capacitors on the board (requires visual inspection by a technician).
- No Backlight / No Picture (but sound is present):
- While the power supply provides power to the backlight inverter, this issue could also be related to the inverter board or the LED/CCFL strips themselves. Consult a technician.
- Smoke or Burning Smell:
- Immediately disconnect the TV from power. Do not attempt to operate it. This indicates a serious component failure and requires professional repair.
For complex issues or if you are unsure about any step, it is highly recommended to consult a professional television repair technician.
9. User Tips
No specific user tips were available from customer reviews or Q&A for this product. However, general advice for electronic components includes:
- Always double-check model numbers and part numbers to ensure compatibility before purchasing a replacement board.
- When replacing, take clear photos of the original board's connections before disconnecting anything.
- Handle the board by its edges to avoid touching components and traces, minimizing the risk of static discharge damage.
10. Warranty and Support
Specific warranty terms for this product are not provided in the available data. For warranty information, technical support, or assistance with installation and troubleshooting, please contact the seller or your point of purchase directly.