B156ZAN04.2 LCD screen panel

Frequently Asked Questions & Solutions

What are the resolution and refresh rate of this screen?

Resolution: 3840(RGB)×2160, UHD, 16:9 | Refresh Rate: 60HZ.

Important considerations:

• Your laptop's graphics chip (GPU) must support this resolution and refresh rate. For example, 4K (3840x2160) requires a GPU with DisplayPort 1.2 or higher, and the LCD cable must have sufficient bandwidth (typically 40‑pin eDP).
• If your original screen was 1366x768 and you install a 1920x1080 panel, the system may work but the BIOS/EDID must recognise the new resolution – some older laptops are locked to the original resolution.
• High refresh rates (e.g., 144Hz) require a compatible cable and graphics output – ensure your laptop supports it.

If you are upgrading to a higher resolution, we recommend checking your laptop's service manual or online forums for confirmed compatibility.

What interface does this screen use, and what are the connector details?

Common interface types for reference:

• eDP 30 pin, Narrow: Width 0.67 inch (17mm), Pitch 0.4mm – common in ultra‑thin laptops.
• eDP 30 pin, Standard: Width 0.75 inch (19mm), Pitch 0.5mm – common in standard 14″–15.6″ models.
• eDP 40 pin, Narrow: Width 0.79 inch (20mm) or 0.83 inch (21mm), Pitch 0.4mm – used for 4K and high‑refresh panels.
• eDP 40 pin, Standard: Width 1.0 inch (25mm), Pitch 0.5mm – used in larger gaming laptops.
• LVDS 40 pin: Width 1.0 inch (25mm), Pitch 0.5mm – older interface, limited bandwidth.

How to verify: Check the connector on your original screen – look for printed labels (e.g., "30P 0.4mm") or measure with a ruler. Compare with our product photos.

If you are unsure, send us a clear photo of your original screen's connector – we can match it for you.

What is the physical size of this screen?

Screen size: 15.6 (measured diagonally).

Important: Even a 0.1‑inch difference can make the panel not fit in your bezel or the mounting holes may not align. Always measure your current screen's active area (visible portion) and outer dimensions (including the mounting tabs).

Additionally, check the aspect ratio – most modern laptops use 16:9, but some use 16:10 (which is slightly taller). A 16:10 screen in a 16:9 bezel will not fit physically, and vice versa.

How to measure: Remove the screen from the laptop and measure the diagonal of the active area (from corner to corner). Also measure the width and height of the entire panel (including the metal frame). Compare these numbers with our product specifications.

Is this a touchscreen?

Touch support: No. This is a standard (non‑touch) panel.

It will work in any laptop that accepts a non‑touch screen. If your laptop originally had a touchscreen, installing this non‑touch panel will result in lost touch functionality (but the display will still work). You may also need to use a non‑touch LCD cable.

What is the grade/condition of this screen?

Grade: Grade A+.

Understanding LCD grades:

• Grade A+ (New): Brand new, flawless panel, zero dead pixels, uniform brightness – the highest quality.
• Grade A (New compatible): New, but may have minor cosmetic variations (e.g., slightly different backlight uniformity) – rarely noticeable.
• Grade B (Used/Refurbished): May have a few (<5) dead pixels or minor scratches that do not affect performance – suitable for budget repairs.

We ship all screens in the grade stated on the product page. All screens are tested for functionality – no lines, no flickering, and backlight is working.

If you require a specific grade, please check the product description or contact us before ordering.

Does this screen have any dead pixels or defects?

All our LCD screens are strictly tested before shipping. They are guaranteed to be free of dead pixels, bright dots, and lines at the time of shipment.

What to do if you find defects after installation:

• Check if the issue is caused by a loose cable – reseat the LCD cable on both ends.
• Test the screen on another compatible laptop (if possible) to isolate the issue.
• If the defects are clearly on the panel (e.g., a cluster of dead pixels or a visible scratch), contact our support within 7 days with photos – we will arrange a replacement or refund.

Our warranty covers manufacturing defects only – physical damage during installation is not covered.

Where is the screen physically located, and how is it attached?

The LCD screen is located inside the display lid (A Cover + B Cover) of the laptop. It is attached as follows:

• To the A Cover (top lid): The screen is usually screwed onto the A Cover using 4‑8 small screws around the edges. Some models use adhesive tape or a metal frame instead of screws.
• Behind the B Cover (bezel): The bezel covers the front of the screen – it must be removed first to access the screen.
• The LCD cable connects from the back of the screen (or bottom edge) to the motherboard, passing through the hinge.
• The screen also has a backlight cable (sometimes integrated with the main cable) that supplies power to the LED backlight.

Accessing the screen requires removing the bezel – some models also require removing the entire display assembly (lid) from the base to avoid damaging cables.

How do I connect the LCD cable to the screen and motherboard?

The connection involves two ends:

• Screen end: The cable plugs into a connector on the back of the LCD panel (or at the bottom edge). This is typically a ZIF (Zero Insertion Force) connector. To connect:
  • Flip up the small locking tab on the screen connector.
  • Insert the cable with the gold contacts facing up (toward the tab) – the cable is often marked with a blue or red stripe to indicate pin 1.
  • Press the tab down firmly to lock.
• Motherboard end: The cable plugs into a header on the system board, usually labelled LCD, LVDS, eDP, or J_LCD. The procedure is the same – lift the ZIF tab, insert the cable correctly, and lock.

Critical: The cable must be inserted all the way – if it is not fully seated, you will get a partial display or no image. Do not force the cable; if it does not go in easily, check the orientation.

Always disconnect the battery before connecting or disconnecting the LCD cable to avoid short circuits.

How to replace the LCD screen step by step?

Note: This is a delicate operation – proceed with caution. If you are not confident, consider using a professional repair service.

1. Preparation: Power off the laptop, disconnect the AC adapter, and remove the battery (if removable). Work on a clean, soft surface.
2. Remove the bezel (B Cover):
   • Use a plastic spudger or guitar pick to gently pry the bezel off – start from the inner edge (near the screen) and work your way around.
   • Some bezels are secured with adhesive – apply low heat (hair dryer) to soften the glue.
   • Be careful not to bend or crack the bezel – it is often thin and fragile.
3. Disconnect the old screen:
   • Locate the LCD cable connector on the back of the screen (or at the bottom). Release the ZIF tab and gently pull the cable out.
   • If there is a separate backlight cable, disconnect it as well.
   • Remove the mounting screws (usually 4‑6) securing the screen to the A Cover.
   • Lift the screen out carefully – avoid flexing it.
4. Install the new screen:
   • Place the new screen in the same position – align the screw holes.
   • Insert and tighten the mounting screws evenly – do not overtighten.
   • Connect the LCD cable – insert it fully into the ZIF connector and lock the tab. Ensure the cable is not twisted or pinched.
   • If your screen has a separate backlight cable, connect it as well.
5. Reattach the bezel:
   • Press the bezel back into place – start from one corner and work around, ensuring all clips snap.
   • If adhesive was used, apply new adhesive tape or use the original adhesive (if still sticky).
6. Test before full reassembly:
   • Reconnect the battery and power on the laptop – check for proper display (no lines, flickering, or dead pixels).
   • Test the brightness adjustment and if touchscreen, test touch functionality.
7. If everything works, power off, disconnect the battery, and reassemble any remaining covers.

Common pitfalls to avoid:

• Forgetting to connect the cable before mounting the screen – you will need to redo the steps.
• Pinching the LCD cable in the hinge area – route it carefully exactly as the original.
• Using screws that are too long – they can damage the screen or the A Cover.
• Not removing all old adhesive – this can cause the bezel to sit unevenly.

Watch our installation video or consult your laptop's service manual for model‑specific details.

What precautions should I take, and what if the screen does not work after installation?

Critical precautions:

• Always disconnect the battery before handling any screen or cable – the LCD backlight can carry high voltage (up to 40V) and can damage the inverter or GPU.
• Handle the screen by the edges – avoid touching the glass surface or the gold contacts on the cable.
• Never bend or flex the screen – the glass can crack easily.
• Use ESD protection – wear an anti‑static wrist strap or touch a grounded metal object before touching components.
• Do not over‑tighten screws – screen frames are delicate; snug is enough.
• Keep the screen clean – any dust or fingerprints on the inner surface will be visible when the backlight is on.

Troubleshooting – what if the screen does not work after installation?

• No display (black screen):
  • Check that the LCD cable is fully inserted and locked on both the screen and motherboard ends.
  • Verify the laptop is powered on (listen for fan or look for caps lock light).
  • Test with an external monitor to confirm the laptop is outputting video – if external works, the issue is with the screen or cable.
  • Inspect the cable for damage – a pinched cable can break internal traces.
• Backlight is on but no image (blank white/grey screen):
  • This usually indicates the video data lines are not connected – reseat the cable, check for bent pins on the connector.
  • Verify that the screen is compatible with your laptop's interface (e.g., eDP vs LVDS).
• Flickering or intermittent display:
  • Check cable routing – it may be pinched in the hinge area.
  • Ensure the cable is not pulled taut – there should be a slight slack.
• Lines, artifacts, or distorted colours:
  • Reseat the cable – sometimes a poor connection causes signal noise.
  • If lines persist, the screen may be defective – contact support.
• Touch not working (for touch screens):
  • Confirm the digitizer cable (if separate) is connected.
  • Install the correct touch driver – some laptops need a specific driver for the new panel.
  • Check BIOS settings – some laptops have a touch enable/disable option.
• Brightness adjustment not working:
  • Ensure the backlight cable (if separate) is connected.
  • Check if the laptop’s brightness keys are functioning – if not, try reinstalling the graphics driver.
• Screen is too dark or uneven backlight:
  • This could be a backlight issue – ensure the connector is fully seated.
  • If the screen is a different model, the brightness levels may be interpreted differently – adjust in the OS.

If you have tried all the above and the problem persists: Contact our support with photos of the screen issue and your laptop model – we will help diagnose and arrange a replacement if necessary.