Pi 400 - Keyboard malfunction
We have observed that, in some cases, the Pi 400 keys malfunction because debris (cardboard, crumbs, dirt) gets trapped in the key mechanism. This will cause this one key not to work, work intermittently, feel spongy or hard. Fear not, this is easily fixed if you are careful!
What to try first
Before disassembling the malfunctioning key, try the safer vacuum cleaner and upside-down shaking. Press the key a couple of times while you do. Doing this could be enough to dislodge the debris that blocks the key from operating normally and free the mechanism. However, if it doesn't fix the problem, try the next steps to see and remove the debris.
The key is still not working
You tried to shake loose the debris but the key is still not working the way it should? You can try to detach the keycap and pick the debris out. Be warned that any damage you do to the keys isn't covered by warranty, but if you are careful and follow the instructions, the chances of damage are slim.
NOTE: The spacebar and shift key mechanisms are MUCH more complex than the other keys. We DO NOT recommend disassembling the spacebar or shift keys.
Key construction
The keycap has two hooks towards the back and two snaps towards the front of the keyboard. The keycap hooks engage two matching hooks on the key scissor mechanism while the snaps attach to posts on the front of the mechanism. To properly engage the hooks, the key has to slide in position at an angle.
What you will need
- A few toothpicks,
- Fine point tweezers.
We use toothpicks so we don't leave marks on the keyboard. Metal tools are very likely to leave scratches and marks that will permanently damage the finish of the keyboard. For this reason, be careful while using the tweezers! They could damage the keyboard membrane or damage the keyboard finish.
I'm ready, what should I do?
Read the entire procedure before starting. If you are not comfortable with the procedure, ask for help!
Here are the steps:
Gently lift the front of the keycap
Using a few toothpicks, gently lift the keycap so we have some space for a toothpick on the side of the key. Use a few to prevent them from breaking and leaving bits in the keyboard.
Gently lift each of the front corners
Insert another toothpick under one of the front keycap corners and gently lift it until it unsnaps. Do one side at a time, being careful to lift only the keycap and not the scissor mechanism.
Angle the keycap and slide towards the front
Holding the key with the front lifted at an angle,
Pull the key towards the front to disengage the hooks.
Lift the keycap from the key cavity.
Remove the debris
Look at the mechanism and identify what is interfering with the key mechanism. It is likely stuck under the scissor of the mechanism.
Now, try to remove the debris by flipping the keyboard upside-down and shaking it a bit. Look if the debris is still stuck in there.
If it is still stuck in there, gently move it where you can grab it with the tweezers and remove it. Be careful not to poke or damage the mechanism or the keyboard membrane under the key.
Verify that the scissor lays flat and that the rubber cap in the middle of the key can be pressed all the way. If they both are, the key should work properly once reassembled!
Reassemble the keyboard
Reassembling the keyboard is easy!
Align the keycap on the scissor mechanism
Put the keycap over the key mechanism and align the hooks in the cavities on the mechanism.
Slide it towards the back
Slide the keycap towards the back of the keyboard. This should engage the hooks of the keycaps to the hooks of the mechanism.
Check the hooks are engaged
Gently lift the front of the key while pushing it towards the back.
Verify that the scissor mechanism lifts at the same time as the keycap. If it does not, try to re-engage the hooks of the keycaps.
If the hooks are engaged and the scissor lifts, lower the keycap while pushing it towards the back.
Snap the keycap back
While the keycap is pushed towards the back, gently press each of the front corners until they snap to the mechanism.
Verify your work
Press down the key and ensure that:
- The four corners go down equally,
- That the corners are level to the keyboard base when depressed.
- The key feels the same as the others.
If you notice that the key isn't right, try the steps again.