The keyboard is an important part of the notebook. It's used by us so frequently that the keyboard 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, specially the key cap falling along. Here post the main phenomenon of the keyboard and their potential problems.
A certain key cannot really enter. If only one key can not be input, the reason could be that the key is invalid or joints didn't welded perfectly. While examine, check whether its contacts is on or possibly 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 the loose weld or metal oxidation.
If the broken keys are neither in the same column, nor in caffeinated beverages contain row of keys can't enter, there may be something wrong with the column line, row line circuit, or logic gateways. 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 not consistent. This may be due to short outlet. Another phenomenon is that pressing a key creates a string of characters. Numerous is caused by a logic circuit fault. First select a column character, if that line doesn't contain a carriage return key column, there end up being several other characters phenomena; if the one the actual Enter key, it may have a character and cannot last into the system bounce phenomenon. Then check logic circuit chip through oscilloscope to find defect. Afterward, the replacement of silicon chips with the models is a good solution.
Sometimes the strong tap is the killer of the Enter key various other shortcuts. As the M35-S320 Laptop Keyboard, it lost the enter key and also the backspace key. The same some game fans, there are four keys should take more attention.