keypad care/hard to press or flickering connection

  • I just followed this "" to clean up my pad .
    (I had to push hard to get response from some pads.)
    and Yes ,I fixed this problem successfully (it was scary ..)but there was one part i was not sure ....

    “junk” can build up on the rubber. one solution to attempt is to disassemble the unit and scour the black pills with fine-grit sand paper.
    ^^^^(this is from docs . i just pasted here.)
    Is this black pills mean square shape inside of pads or very tiny things on the green board ?

    I scoured both of them this time.

    I'm sorry English is my 2nd language and I'm still learning.
    I would like to figure out this for next time.

    Thank you for your help.:)

  • the black pills are the square contacts inside the pads. those things on the board are diodes.

  • Thank you very much @elquinto.
    I'm very clear about this right one now.:)
    I was only cleaning half of them last night .
    I can do other half with out fear tonight:)