Keyboard for Asus G550 G550JK N550 backlit 90NB04L3-R31FS0

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PCS pcspare.com
ID: PCS-20162 Type: keyboard only Model/PN: 90NB04L3-R31FS0 Layout: Farsi FS State: Discount Backlit: YES Condition: NEW
Availability: In Stock
‌EUR € 18.00
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Keyboard — Exploded View

A PRESS LED ⑤ Keycap ④ Scissor ③ Backlight ② Frame ① Membrane How It Works Key press → Scissor collapses → Membrane contacts close → Signal sent. Backlight: LED + light guide plate illuminates translucent keys. All layers pre-integrated — just connect the ribbon cable.

Frequently Asked Questions & Solutions

What is the layout of this keyboard?

The layout of this keyboard is Farsi FS.

Common layout types:
  • US (United States): Standard QWERTY, wide horizontal Enter key, left Shift key is long, backslash key above Enter.
  • UK (United Kingdom): QWERTY, tall vertical Enter key, left Shift key is shorter, backslash key near left Shift.
  • DE (German): QWERTZ layout, with umlaut keys (ä, ö, ü).
  • FR (French/AZERTY): AZERTY layout with specific French characters.
  • JP (Japanese): QWERTY with additional keys for Japanese input (including Kana toggle).
  • ES (Spanish): QWERTY with ñ key and specific accent keys.

Important: Layouts are not interchangeable – the key positions, Enter key shape, and modifier key sizes vary. Installing a US keyboard on a UK laptop will result in some keys not matching the keycaps, and the operating system may map the keys incorrectly (though you can change the keyboard layout in software).

How to verify: Check your original keyboard – look for the Enter key shape (wide horizontal vs tall vertical) and the position of the backslash key. If unsure, send us a photo of your original keyboard and we will confirm the layout.

Does this keyboard support backlight?

Yes, this keyboard is backlit.

Important compatibility notes:
  • Your laptop must have a backlight connector on the motherboard – it is usually a separate 2‑pin or 4‑pin cable (often labelled KB_BL or J_BL).
  • If your laptop does NOT have a backlight connector, installing this keyboard will result in no backlight – the keys will still function normally, but they will not light up.
  • Some laptops require a BIOS setting to enable backlight – check your laptop's BIOS or UEFI settings (usually under "Keyboard" or "System Configuration").
  • The backlight brightness is often controlled by Fn + F10 (or similar combination) – test this after installation.

Connection: If your keyboard has a separate backlight cable, connect it to the designated motherboard header. If the backlight is integrated into the main ribbon cable, no additional connection is needed.

If you are replacing a non‑backlit keyboard with a backlit one, make sure your laptop's motherboard has the necessary connector – otherwise the backlight will not work.

What connector type does this keyboard use, and how do I install it correctly?

This keyboard uses a N/A interface (common types include ZIF, FPC, or ribbon cable with 0.5mm or 0.4mm pitch).

Critical – connector orientation:
  • When connecting the ribbon cable to the motherboard, ensure the metal contact pins face the correct direction (usually downward or upward depending on the ZIF latch type).
  • Look at your original cable before removal and note the orientation – or take a photo for reference.
  • Reversing the cable (inserting it upside‑down) can damage the connector or cause the keyboard to not function – in some cases, it can short‑circuit the motherboard.
  • Always push the cable fully into the socket until it stops, then secure the locking latch (flip it down) before powering on.
  • The cable should be straight – not twisted or folded near the connector.

If the cable has a reinforcing strip (a thicker plastic piece at the end), ensure this strip is positioned correctly – it usually indicates the insertion depth and orientation.

If you are unsure about the correct orientation, our installation video and photos can guide you – or contact our support for assistance.

Are there any physical differences I should check before buying?

Yes – please verify the following physical attributes to ensure a perfect fit:

  • Frame (metal/plastic backing):
    • Some keyboards come with a metal reinforcement frame that screws into the chassis.
    • Others are frame‑less and held by clips/adhesive.
    • Check if your original keyboard has a frame – if not, you may need to transfer your existing frame. Our product description indicates has frame: N/A – compare with your original.
  • Enter key shape:
    • US layout: Wide horizontal Enter key (often called "ANSI Enter").
    • UK / EU layout: Tall vertical Enter key (often called "ISO Enter").
    • These are not interchangeable – the chassis has a cutout for the specific shape.
  • Keycap profile: Some keyboards have a different keycap curvature – while rare, some high‑end laptops use custom key shapes (e.g., Lenovo ThinkPad has a distinctive concave key cap).
  • Color / finish: This keyboard is Black – ensure it matches your laptop’s aesthetic. Some models come in silver or white.
  • Screw hole positions: The mounting points (screw holes or clips) must align with your chassis – compare your original keyboard's backside with our product photos.
  • Touchpad integration: Some keyboards are part of a larger palmrest assembly – these are not standalone keyboards. Ensure you are buying the correct part type.

Part number (PN) check: The PN on the back of the keyboard may differ from your original, but we guarantee full compatibility if the model and layout match. If you are unsure, send us a photo of the back of your original keyboard (showing the PN sticker) and we will confirm.

Is this keyboard compatible with my laptop?

This keyboard is designed for models matching 90NB04L3-R31FS0.

To verify compatibility, please check the following:
  • Laptop model number: Your laptop's full model number (e.g., "Dell Latitude 3540", "HP EliteBook 840 G5", "Lenovo ThinkPad T480") must match our product listing.
  • Layout: Confirm the layout type (US, UK, DE, JP, etc.) matches your original keyboard.
  • Connector type: The cable connector (pitch and pin count) must match the motherboard header.
  • Frame type: Ensure the keyboard includes the frame type your laptop requires (metal frame vs. frame‑less).
  • Backlight support: If you need backlight, ensure the keyboard is backlit and your motherboard has the backlight connector.

Important note on model variants: Some laptop models have different keyboard variants depending on the region and configuration (e.g., some have backlit, some do not; some have a fingerprint reader, some do not). Always check your original keyboard's features before ordering.

If you are unsure, contact our support with your laptop's exact model number and a photo of your original keyboard – we will confirm compatibility for you.

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

The keyboard is located on the upper chassis (C Cover / Palmrest) of the laptop – it is the main input surface you type on.

How the keyboard is attached (two common methods):
  • Method 1 – From the top (keyboard side):
    • The keyboard is inserted from the top of the C Cover.
    • It is held in place by clips and/or screws accessed from the bottom of the palmrest.
    • Removal requires prying the keyboard up from the top side – often using a spudger to release the clips.
    • This is the most common method in modern laptops.
  • Method 2 – From the bottom (D Cover side):
    • The keyboard is secured by screws from the underside of the motherboard (you need to remove the bottom cover to access them).
    • The keyboard drops out from the top once the screws are removed.
    • This method is common in older or business‑class laptops (e.g., older ThinkPads).

The keyboard connects to the motherboard via a ribbon cable that passes through a slot in the C Cover, plugging into a ZIF connector on the motherboard (usually labelled KEYBOARD, KBD, or J_KB).

Access: To replace the keyboard, you may need to remove the bottom cover (D Cover) or the bezel around the keyboard – depending on the model. Some laptops require removing the entire palmrest (C Cover).

Always consult your laptop's service manual for the specific removal method – forcing the keyboard can damage the clips or the C Cover.

How do I identify the motherboard keyboard connector and connect the cable?

The keyboard cable plugs into a dedicated header on the motherboard. It is usually located near the edge of the motherboard (closest to the keyboard area). Common silkscreen markings include:
  • KEYBOARD / KBD
  • J_KB / J_KEYB
  • KB1 / KBC (Keyboard Controller)
  • EKB (Embedded Keyboard)

Connection procedure:

  • Identify the ZIF (Zero Insertion Force) connector on the motherboard – it usually has a small brown or black locking flap.
  • Flip up the locking flap (gently, with a fingernail or spudger).
  • Insert the keyboard ribbon cable into the slot – ensure the metal contact pins face the correct direction (usually facing away from the flap or facing towards the flap – check your original cable orientation).
  • Push the cable all the way in – it should not have any slack.
  • Press the locking flap down to secure the cable – you should feel a click.

If the keyboard has a separate backlight cable:

  • This cable plugs into a separate connector on the motherboard – usually labelled KB_BL, J_BL, or BACKLIGHT.
  • It is often a 2‑pin connector – connect it with the correct polarity (the red wire is usually positive).
  • Not all laptops have this connector – if yours does not, the backlight will not work.

Do not force the cable – if it does not go in easily, check the orientation. Bent pins on the motherboard header can be difficult to repair.

How to replace the keyboard step by step?

Note: Keyboard replacement methods vary by laptop model. The steps below are general – refer to your laptop's service manual for model‑specific instructions.

Step 1: Preparation

  • Power off the laptop, disconnect the AC adapter, and remove the battery (if removable).
  • Press the power button for 5 seconds to discharge residual power.
  • Work on a clean, soft surface.
  • Have a plastic spudger and a small Phillips screwdriver ready.
  • Take photos of the keyboard and cable routing before you start.

Step 2: Remove the old keyboard

For top‑mount keyboards (most common):

  • Remove the bottom cover (D Cover) and locate the screws securing the keyboard (usually marked with a keyboard icon on the motherboard or bottom cover).
  • Remove these screws – the keyboard should now be free from the bottom.
  • From the top side, gently pry the keyboard up using a plastic spudder – start from the top edge (near the screen) and work around the clips.
  • Lift the keyboard slightly and disconnect the ribbon cable from the motherboard (flip up the ZIF latch, pull the cable out).
  • If there is a separate backlight cable, disconnect it as well.

For bottom‑mount keyboards:

  • Remove the bottom cover (D Cover).
  • Remove all screws securing the keyboard from the underside (they are usually clearly visible).
  • Push the keyboard up from the bottom – it will pop out from the top side.
  • Disconnect the ribbon cable and backlight cable from the motherboard.

Step 3: Transfer components (if needed)

  • If your new keyboard does not include a metal frame but your original did, transfer the frame from the old keyboard to the new one.
  • Ensure the frame is seated correctly and all screw holes align.

Step 4: Install the new keyboard

  • Connect the ribbon cable to the motherboard first (before placing the keyboard in position) – this is easier and avoids pulling the cable later.
  • Ensure the cable is fully inserted and the ZIF latch is locked.
  • If there is a backlight cable, connect it to the backlight header.
  • Place the keyboard into the chassis – align the clips or screw holes.
  • Press the keyboard down firmly to engage all clips (you should hear them click).
  • Secure the keyboard from the bottom (if screws are used) – do not over‑tighten.

Step 5: Test before full reassembly

  • Reconnect the battery briefly, power on the laptop.
  • Test every key – use a keyboard testing website or Notepad to check all keys (including Fn keys, arrow keys, and special characters).
  • If backlit, test the backlight function (Fn + brightness key).
  • If all works, power off and disconnect the battery.

Step 6: Reassemble

  • Reattach the bottom cover (D Cover) and all screws.
  • Replace the battery and AC adapter.

Common mistakes to avoid:

  • Forgetting to connect the cable before fully placing the keyboard – you may need to remove it again.
  • Inserting the ribbon cable upside‑down – always note the original orientation.
  • Using excessive force when prying the keyboard – this can break the clips or crack the C Cover.
  • Losing small screws – use a magnetic tray to keep them organized.

If you are unsure about any step, watch our installation video or consult your laptop's service manual.

What precautions should I take, and what if some keys do not work after installation?

Critical precautions:

  • Always disconnect the battery before handling the keyboard cable – the keyboard controller can be damaged by static or residual power.
  • Handle the ribbon cable gently – it is fragile. Do not bend it sharply or pull on it.
  • Do not touch the gold contacts on the ribbon cable – fingerprints or oil can cause poor contact.
  • Use the correct screws – keyboard screws are often shorter than others. Using a longer screw can puncture the keyboard membrane or damage the chassis.
  • Avoid spilling liquids – a spill can damage the keyboard membrane.
  • Check the cable routing – ensure the cable is not pinched by the chassis or any other component.

Troubleshooting after installation:

  • No keys work at all:
    • The ribbon cable may be loose or upside‑down – reseat it carefully, ensuring the metal contacts face the correct direction.
    • Check if the ZIF latch is fully locked – if it is not, the cable will not make proper contact.
    • Inspect the cable for damage (tears or bent contacts).
    • If the cable is damaged, you may need a replacement.
  • Some specific keys do not work:
    • Check for debris or dust under the keycaps – use compressed air to clean.
    • If the same key on multiple rows is not working, the membrane circuit may be damaged – this could be a manufacturing defect.
    • Test the keyboard on another laptop (if compatible) to isolate the issue.
  • Keys are sticky or hard to press:
    • There may be debris under the keys – gently remove the keycap (if it is removable) and clean underneath.
    • If the keyboard is new, some keys may feel stiffer initially – they should loosen with use.
  • Keyboard types wrong characters:
    • Your operating system is set to a different layout – go to Settings → Time & Language → Language & Region, and select the correct keyboard layout (US, UK, DE, etc.).
    • If the layout is correct but still typing wrong characters, the keyboard may be physically mislabeled – check the keycap markings against your expected layout.
  • Backlight does not work (for backlit keyboards):
    • Verify the backlight cable is connected (if separate).
    • Check the BIOS – some laptops have a backlight enable/disable setting.
    • Check the Fn + brightness key – often Fn + F10 or Fn + spacebar.
    • If your laptop originally did not have a backlight, the motherboard may lack the backlight connector – the keyboard will work, but the backlight will not.
  • Keyboard flexes or moves when typing:
    • Some screws may be loose – recheck all keyboard screws.
    • If the keyboard is clipped in, ensure all clips are fully engaged – press down firmly around the edges.

If the problem persists: Contact our support with details about which keys are not working and photos of your keyboard installation – we will help diagnose if the keyboard is defective or incompatible.

Do I need to install drivers or change settings for the new keyboard?

For most laptops, no driver installation is needed – keyboards are standard HID (Human Interface Device) and are automatically recognized by Windows, macOS, and Linux.

However, there are a few exceptions:

  • Special function keys: Some laptops (e.g., Dell, HP, Lenovo) have custom function keys (brightness, volume, airplane mode) that require the manufacturer's keyboard driver or utility software (e.g., Lenovo Hotkey Features, Dell Power Manager, HP System Control). If these keys do not work, download and install the latest driver from the manufacturer's support page.
  • BIOS update: Some newer keyboards require a BIOS update for full compatibility – especially if you are replacing a non‑backlit keyboard with a backlit one (or vice versa).
  • Keyboard layout: If the physical layout (US vs. UK) differs from your OS setting, you may need to change the input language in your operating system settings.
  • Fn key mapping: Some laptops have a Fn key that can be locked or unlocked via BIOS or software – check your laptop's documentation if the Fn key behaviour seems different.

Step‑by‑step for Windows users:

  • After installation, boot into Windows and check if all keys work.
  • If special keys (volume, brightness) do not work, go to the manufacturer's support website and download the keyboard driver or system utility.
  • Install the driver and restart the laptop.
  • If the keyboard layout is wrong, go to Settings → Time & Language → Language & Region → Preferred Language → Options → Add a keyboard, and select the correct layout.

If you are using Linux or macOS, the keyboard should work plug‑and‑play – you may only need to adjust the layout settings in the system preferences.