Laptop keyboards: signs of failure and how to choose the right layout and fit

What a laptop keyboard is made of

A laptop keyboard is a thin assembly of keys, a membrane that registers each press, a metal or plastic support plate and, on many models, a backlight layer. It connects to the system board through one or more ribbon cables. Some keyboards are a separate part held in by screws or clips. In many recent laptops the keyboard is riveted or glued to the top cover, and the replacement part is the whole top cover with the keyboard already fitted.

How do you know the keyboard needs replacing?

• One or more keys do not respond, or only respond when pressed hard.
• Keys type on their own or repeat without being pressed.
• A whole row or group of keys fails at once, which usually points to the membrane or the cable.
• Keycaps or the small hinges under them are broken or missing.
• The backlight no longer works on all or part of the keyboard.
• Keys have become sticky or unreliable after a liquid spill.

Try these first

Before replacing the keyboard, plug in an external keyboard. If it works normally, the laptop itself is fine and the fault is in the built-in keyboard or its cable. Restart the laptop and update its drivers, because a software fault can also make keys misbehave. A single sticky key can often be cleaned, but liquid damage under the keys usually spreads to the membrane, and replacing the keyboard is then the reliable fix.

How to choose the right keyboard

• Read the part number on the label underneath your keyboard, or on the inside of the top cover. It is the surest match.
• Otherwise use the laptop's exact model or product number, from the label underneath the laptop, or its serial number. Models in the same series often use different keyboards.
• Match the layout. The same laptop is sold with keyboards for many languages, and they differ in the shape of the Enter key, the position of some symbols and the letters printed on the keys.
• Check whether yours has a backlight and whether it has a pointing stick in the middle of the keys, and buy the same.
• Check whether the part is the keyboard alone or the whole top cover with the keyboard fitted, and which one your laptop needs.
• HP spare numbers end in a three-digit code that usually identifies the language, for example -001 for US English. Lenovo FRU numbers and Dell part numbers also differ by layout, so a number from the same series with a different ending may be a different language.

Fitting tips

• Shut the laptop down, unplug it and disconnect the battery before you start.
• Ribbon cables lock into the board with a small latch. Open the latch before pulling the cable, and close it again after inserting the new one.
• Keyboards held by tabs along the top edge are released from the top. Work slowly to avoid bending the new keyboard.
• If the replacement is a full top cover, the touchpad, speakers and other parts may need to move across from the old cover.