How to fix PC Keyboard Circuit Board ?

Discussion in 'General Electronics Chat' started by ssparkss, Apr 13, 2010.

  1. ssparkss

    Thread Starter New Member

    Apr 13, 2010

    Instead of purchasing a new keyboard I would like to fix the ones I have (2).

    Whilst cleaning one out I mistakenly reversed the power connection, and heard a pop. Can't see any fuse's or anything that is broken/burnt. Does anyone know which component I would need to replace ?

    Any help would be appreciated, thanks.
  2. BMorse

    Senior Member

    Sep 26, 2009
    How do you reverse power to a keyboard?? I have been working with PC's for as long as I can remember, but this is a first for me.... what type of keyboard is it? What type of connection does it have (i.e. PS2, USB, etc...)?

    If by chance you had it open, and you plugged in the connector to the internal circuit board (which you would have to force the connectors together since they are most likely a mating pair with polarized keys or detents to prevent them from being connected backwards....), then you most likely fried the main controller IC.... they usually don't integrate any kind of protection for reverse connection of the power source, since under normal use it would be hard for someone to connect the power incorrectly.

    Post pictures of the circuit board in question.... include top and bottom pics, and as clear as possible. This would help in determining if there could be something else to check.

    My .02
    B. Morse
  3. retched

    AAC Fanatic!

    Dec 5, 2009
    I would be VERY interested to see how this was managed also. If you fried the controller, you >could< repair it... it would be iffy.
  4. ssparkss

    Thread Starter New Member

    Apr 13, 2010
    Hi BMorse
    thanks for the response.

    Full newbie here ha. 'reversing the power', was my terminology to show what a monkey i am. See pictures.

    1st picture is the original setup, the 2ND pic shows the black connector the other way around.

    Keyboard is an HP KU-0133

    Thanks heaps
  5. BMorse

    Senior Member

    Sep 26, 2009
    By reversing the connector you may have very well fried the controller, which unfortunately is under that "black" blob..... no way to replace or "fix" those....
    looks like you will have to spend another $12.00 on a new multimedia keyboard ;) .

    B. Morse
  6. SgtWookie


    Jul 17, 2007
    Yep, it's a "binner" - for those of you unfamiliar with UK slang, that means it's ready for the dust bin, also known as a trash can.
  7. atferrari

    AAC Fanatic!

    Jan 6, 2004
    You say you have 2 to repair?

    Have you blown both of them in the same way? Too bad that you insisted...
  8. Jazz Bass Special

    New Member

    Apr 9, 2010
    I wonder how much HP "saved" by using that connector.
    Non-polarized connectors are rare now a days.
    I like the bottom view of the circuit board.
    All those leads laid over onto a different buss.
    I cannot count how many of these "laid overs" I have lifted over the years on different pieces of equipment.
    The last layer of a PC board is called the solder mask.
    Where you want solder, the copper is exposed.
    Where you do not want solder, it is masked.
    The masking "acts" as an insulator until it burns through the masking.
    Too many manufacturers get away with murder by sloppy assembly practices like this. (poor preheating of the boards before wave soldering is another)
    I had a customer that brought in a 20 year old PLC that went poof.
    A 12 volt lead was laying on the ground buss.
    Hey, it passed inspection!
    20 years later, the smoke came out.