While disassembling a Sega Saturn to clean it, I removed this power switch:

enter image description here

I needed to separate the top grey button (1 in the image) from the rest of the switch.

After verifying with a multimeter that there wasn't any dangerous current on these components, I pulled like an idiot piece 1 with a lot of strength, and I think piece 2 made a sort of clicky noise, only to realized it would have been sufficient to widen the clips underneath the button to remove it easily.

I reassembled the Saturn, all works perfectly except for this switch, which I suppose have been mechanically damaged. When I press the power button 1, the console turns on, but only while I keep the button pressed. As soon as I release it, the Saturn turns off. I tried to tape the button down and it works indefinitely, until I remove the tape.

I would happily buy a replacement, but I can't seem to find it anywhere, and buy a broken console just to replace this seems like a total waste to me.

I have some questions:

  1. what component is the black box (2)? I can solder, so I thought I could replace only that part, but I can't find anything similar. I'm a noob in electronics, is it a relay? I need the keyword to search for this piece. My understanding is that this thing has two states, which are toggled when pressing the button (piece 1), but now the state doesn't toggle and I need to keep it pressed down to have it "on".

  2. Until I find a solution, is keeping the button taped down dangerous for me or the console? Can this cause more damage?

  3. Is there a DIY solution to try to fix this thing given that is broken already? Heating, freezing, shaking, or other arcane methods from forbidden magic?

  4. Bonus question: is the blue round component (piece 3) a capacitor?

  • \$\begingroup\$ 1. A latching switch. 2. No problem. 3. Isn't it just a mechanical problem where you are unable to press it deep enough to latch? 4. Probably a Y-capacitor. \$\endgroup\$
    – winny
    Commented Mar 25, 2021 at 11:34
  • \$\begingroup\$ Thank you for your answer. I thought too it wasn't going deep enough, I tried pressing very hard, but the result its still the same. The feeling however is exactly that of a button that is not pressed enough to stay on (however it clicks). I don't know if pushing even harder could fix it, but I'm afraid to break it even more. \$\endgroup\$
    – John
    Commented Mar 25, 2021 at 12:26
  • \$\begingroup\$ Bummer. I would try to open it and repair if possible, otherwise replace it. \$\endgroup\$
    – winny
    Commented Mar 25, 2021 at 12:59
  • \$\begingroup\$ Yeah I would try to open it before replacing it. Is it a safe component to handle? I read a 250v on the side, but I suppose is the current it is able to handle, not a stored voltage like in a capacitor, am I correct? \$\endgroup\$
    – John
    Commented Mar 25, 2021 at 13:03
  • \$\begingroup\$ @mars yes switches are safe to handle. Pretty much everything except capacitors. Note that capacitor charge can go through the wires to other parts, of course, so you should discharge capacitors even if you aren't working on capacitors. \$\endgroup\$ Commented Mar 25, 2021 at 15:29

1 Answer 1


Just make sure the device is unplugged while working on it. The switch just serves to pass the hot phase to the device. You probably bent an internal contact in the switch, or deformed some plastic component that holds the switch latched. If you don't mind loosing the on-off switch, I'd just solder together the switch input-output, meaning once plugged in the machines is always on, you'd have to unplug it to turn off. Otherwise you can just replace the switch with any other 2A mains rated switch, might not look original but maintains functionality. The blue capacitor across the contacts really only serves to stop ripple from the mains, and is not indispensable, so if you replaced the switch it wouldn't be mandatory to transfer the capacitor.

  • \$\begingroup\$ I think the asker is more worried about the safety of the blue thing, than whether it's essential to the circuit \$\endgroup\$ Commented Mar 25, 2021 at 15:30
  • \$\begingroup\$ @user253751 Yeah, I was worried about both my safety and the role of the capacitor in the circuit:) \$\endgroup\$
    – John
    Commented Mar 31, 2021 at 19:20
  • \$\begingroup\$ Thank you for your answer, I was in fact thinking about make it permanently on and just unplug it to turn it off. What you mean is that I should bridge the two leads of the switch? Basically the two leads connected by the blue capacitor, but directly connected? Or solder the two parts on the actual PSU that are connected to the switch's wires? \$\endgroup\$
    – John
    Commented Mar 31, 2021 at 19:24
  • 1
    \$\begingroup\$ @mars I think they mean solder together the contacts that the switch connects when it's turned on. It looks like the switch only has two contacts, so they'd have to be the correct two \$\endgroup\$ Commented Mar 31, 2021 at 22:07

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