The situation when a key falls off a laptop is familiar to many users, from beginners to experienced engineers. This is not only annoying when typing, but can also lead to dust and crumbs getting under the mechanism, which will cause the entire matrix to break down in the future. Often the problem can be solved independently, without contacting a service center, if you know the design features of a particular device.
The main difficulty is that the key mechanisms vary greatly between different manufacturers and even between different series of the same brand. What worked for HP Pavilionmay not be suitable for Lenovo ThinkPad. Incorrect actions can lead to breakage of the fragile plastic latches, and then you will have to change not only the button, but also the substrate, which is much more expensive.
In this article we will analyze the main types of mechanisms, tools for work and a step-by-step recovery algorithm. You will learn how to distinguish a scissor mechanism from a membrane one and what mistakes are most often made when trying to insert a key back.
Determining the type of keyboard mechanism
Before trying to insert the key back, you need to carefully examine the place where it was located and the key itself. The entire further algorithm of actions and the choice of tools depends on the type of mechanism. Most modern laptops use a scissor mechanism, which provides short strokes and reliability, but there are exceptions.
Carefully inspect the base of the laptop case. If you see two plastic crosses connected to each other and metal brackets on the sides, this is a classic scissor mechanism. Sometimes there are also plastic βantennaeβ on the base, which serve as stops for the key itself. In this case, you will need to align these elements with the corresponding grooves on the bottom of the key.
If under the key you see just a rubber membrane with a plastic cap or cone, then in front of you membrane mechanism. Such keyboards are often found in budget models or older devices. Inserting a key here is easier, since there is no complex system of plastic levers, but care is required so as not to tear the rubber cap.
- Scissor (plastic christening)
- Membrane (rubber cap)
- Micromechanical (backlight)
- I don't know, I'll have to look
Tools and workplace preparation
For safe repairs, you will need a minimum set of tools, which you most likely already have in your home. The main rule is to work on a clean, level surface with good lighting. Dust and debris can get under the keyboard during repairs and cause new contact problems.
You will definitely need thin screwdriver or a plastic pick. Use metal objects with extreme caution to avoid scratching the case or damaging the contacts. Fine-tipped tweezers are also useful for removing small parts and pieces of debris from under the keys.
Do not use knives or blades to pry the keys, as they can easily damage the plastic latches. If the key has fallen off along with the plastic mechanism, you may need a drop superglue (but only if you are confident in your skills) to repair a broken latch. However, in most cases no glue is needed.
βοΈ Preparing for key repair
Key insert with scissor mechanism
This is the most common type of mount in modern laptops such as Asus ZenBook or Dell XPS. The process requires care and patience, as the plastic latches are very fragile and easily break if too much force is applied. First you need to install the plastic βscissorβ itself in place.
If the scissor mechanism remains attached to the keyboard, make sure it is aligned correctly. The upper part of the mechanism must be pressed against the plastic stops on the body, and the lower part must be free to move. If the mechanism has completely fallen off, it must be put on two metal brackets fixed to the board until it clicks.
The key itself is placed on top of the mechanism. First, slide the top edge of the key over the plastic tabs or scissor hooks, then gently press the bottom edge until it clicks. If there are metal brackets on the sides, make sure they engage the grooves on the key.