Servicing a Game boy DMG (Original)

Discussion in 'Other Handhelds' started by Pokepicker, Jun 19, 2017.

  1. Pokepicker

    Pokepicker GBAtemp Regular

    Nov 2, 2015

    I recently acquired a fairly cheap Game boy DMG. It was in a worse shape then the images and description would lead one to believe.
    So I decided this device was in need of some tender loving.

    I opened the case, and removed the PCB so I could clean the outer shell itself. At the same time I washed the buttons, as well as fixed a bunch of dead vertical columns. Great success. The shell looks nicer, the buttons are less gross and the screen is back to it's old glory days.

    I still have two issues with this device.
    1: The battery connectors are dirty/damaged from what I would guess was a leaky battery.
    - Ordered new ones as cleaning them didn't really work out that well. I'm guessing the dirty connectors might be why the machine will not always turn on. If it is reluctant to turn on, wiggling the batteries a little make it work.
    Luckily I can't see any damage on the PCB itself.​

    2: The buttons are unresponsive.
    - I never tested the buttons before fixing the screen, but after assembling the Game boy after it's cleaning process, the buttons don't work.
    Someone recommended that I take some paper and rub on the black spots on the back of the rubber pads. I re-opened my DMG, loosened the PCB with the LCD on it from its case and rubbed the black spots on the rubber pads.
    Putting the PCB half way back in place (just a couple screws holding it), I started the Gameboy again to test. Now it seemed like it was pressing buttons "at random", or more likely it was highly sensitive. I figured that was a good sign. At least it was doing something when having its buttons pressed.

    After I assemble it again, the buttons are again completely dead. A/B, SELECT/START and possibly the D-pad (unknown since I cant press my way passed any Title screen and thereby be able to test the arrows).

    I have ordered a new set of rubber pads. I really hope this will work. But in the case it does not, what should I do? Someone also recommended that I clean the PCB in the area where the rubber pads would be making contact. What should I use to clean the PCB?​
  2. britain4

    britain4 GBAtemp Regular

    Jun 16, 2014
    I would use rubbing alcohol on a cotton bud to clean the connectors on the PCB, or alternatively a pencil eraser.

    Try the same thing on your rubber pads and you might find they will start working properly again. If not, the new set of pads should fix it. If it still doesn't work there may be damage to the board somewhere but I would say unlikely
  3. Pokepicker

    Pokepicker GBAtemp Regular

    Nov 2, 2015

    I really hope the new rubber pads are going to help.
    Tore down the DMG again, cleaned both the button area of the PCB as well as the black pads on the rubbers.
    No improvement.

    I asked a similar question in some FB group where someone mentioned the CPU could be damaged if the ribbon connector is removed while the Gameboy is powered on.
    I'm going to hope this is not the case, as I haven't done it. And I'm doubtfull that the previous owner has had the case open and done any work.

    Now I have never seen a DMG with a damaged CPU, but I hope it is ok.
    I find it strange the buttons kinda worked while having the PCB loose in the case. But upon screwing the PCB in place the buttons quit responding.

    Is the CPU even replacable if that is the faulty part, or is the PCB more or less junk at that point?