The keyboard is an important part of the notebook. We use it so frequently that it has different problems. The common keyboard faults are mainly caused by circuit fault, the keyboard hats off, poor contact, and oxidation. One had a Toshiba satellite M35-S320 Laptop Keyboard
to repair, it was full of problems, especially the key cap falling down. Here post the main phenomenon of the keyboard and their potential causes.
A certain key can not enter. If only one key can not be input, the reason may be that the key is invalid or joints didnít welded perfectly. While examine, check whether its contacts is on or not. If the key pressed has no conduction, the key must be at poor contact, which requires repair or replacement. If the contact is ok, that could be the loose weld or metal oxidation.
If the broken keys are neither in the same column, nor in the same row of keys canít enter, there may be something wrong with the column line, row line circuit, or logic gates. This state can be detected by 100MHz oscilloscope to find the troubled point, and then repair the laptop keyboard.
Keyboard input and screen display of the characters are inconsistent. This may be due to short circuit. Another phenomenon is that pressing a key produces a string of characters. This phenomenon is caused by a logic circuit fault. First select a column character, if that line does not contain a carriage return key column, there could be several other characters phenomena; if the one with the Enter key, it will have a character and can not last into the system bounce phenomenon. Then check logic circuit chip with an oscilloscope to find fault. Afterward, the replacement of silicon chips with the new models is a good solution.
Sometimes the strong tap is the killer of the Enter key and other shortcuts. As the M35-S320 Laptop Keyboard
, it lost the enter key and the backspace key. And for some game fans, there are four keys should take more attention.