iFixit - Answers With Device "Sega Genesis"

Sega Genesis: Bad, Noisy, buzzy sound

Thu, 28 Jul 2022 10:25:33 -0700

Hi!

Today I plugged my old sega genesis (I'm writing from Portugal, here we call it mega-drive), didn't use for at least 10 years. The last time I used it, it was good, I'm almost shure didn't have any problem.

Today, I plugged it and I notice the image was bad, but the worst part was the sound. I'm gonna try to describe the best I can, with my bad english, the sound was buzzy, noisy... I thought it could be a problem with the tv, or the cable, so I plugged my headphones to the genesis, and it was the same. I'm sure the problem is with the console.

I've read it could be the voltage regulator, is there any way to test them? DO you have any idea of what could be?

⟐ Commented July 28, 2022 at 10:25 MST

Sega Genesis: Power switch only works sometimes

Fri, 19 Aug 2022 22:46:58 -0700

I have a Sega Genesis (model 1) that has some issues with the power switch only turning on sometimes. It takes a few tries of turning it on and off again before the on light even comes on at all, but even then it doesn’t come on in the on position, only when I’m halfway through turning it off again. With enough back and forth it does come on properly, but it’s been taking progressively more time for it to do this (was fine when I pulled it out of storage ~5 months ago).

I’ve also noticed it’s got some other issues. The video kind of flashes brighter and darker on some scenes, mostly on menus. My other tv shows wavy lines that get worse the longer you play. Probably just the tv, but it’s annoying nonetheless.

I’m currently using an adapter I got at Goodwill, not meant for the system but it’s the right voltage, amps, and I’ve switched it so the polarity is right. I’ve had the entire system apart and made sure the outside part of the switch was lined up with the inside. Everything looked fine inside, nothing damaged. I’ve cleaned the adapter in port in case that was corroded. I’ve tried moving the wires around in case of there being a loose connection, same thing with the tip of the adapter. I’ve tried the adapter from my Sega CD (it seems to fit better). It could be something just inside the console because once I accidently touched the adapter tip while it was on and it rebooted, but I really don’t know. Any ideas?

Edit: Circuit board

⟐ Commented August 19, 2022 at 22:46 MST

Sega Genesis: Why can't any controller plugged in as the first controller press up?

Thu, 28 Jul 2022 10:38:52 -0700

So I can use up on all my controllers in the 2nd controller slot so I know the controllers are fine. But whatever controller is in the first slot doesn't allow me to press up. I'm guessing there's something wrong with the connectors so I'm just wondering if I should just replace the whole thing or if there's an individual pin I could fix.

⟐ Answered July 28, 2022 at 10:38 MST

Sega Genesis: Model 1 board, does this look normal?

Sun, 08 Mar 2026 19:20:15 -0700

I took apart My model 1 to clean it up etc and while looking around I came across a spot where it looks like a trace was damaged. I’ll post pics of the top and bottom of the board so you can see. The spot in question is circled in red.

So I somehow found a post on sega-16 about a genesis with a resistor on the bottom with a cut trace, exactly like mine. I'm starting to think this was just some factory "fix" or "repair" rather than a mod. Second post has a working image link which shows the same kind of resistor on the same spot with the trace cut.

https://www.sega-16.com/forum/showthread...

⟐ Commented March 08, 2026 at 19:20 MST

Sega Genesis: Genesis won't play video.

Thu, 02 Jan 2020 06:40:23 -0700

So my genesis 2 wont play the games. I've cleaned it with a credit card and cloth/alcohol and the games. All it does is flash around the screen a few times and goes black. I don't know what's wrong.

⟐ Answer deleted January 02, 2020 at 6:40 MST

Sega Genesis: Controller port 1 is iffy at best. How can I fix this?

Thu, 05 Jul 2018 07:21:03 -0700

Recently picked up a free genesis out of the trash. Everything about it works fine, except the first controller port. I'm guessing the pins aren't connecting right, because every controller i've tried with it has the same problem. If anyone has had a similar problem or knows how to fix this please let me know.

⟐ Answered July 05, 2018 at 7:21 MST

Sega Genesis: I found this Genesis with no games, do I need a game to power it on?

Wed, 08 Nov 2023 21:37:31 -0700

I have all I need for it but a game, do i need a game to have it turn on or show the red light or can it show me some life without it?

⟐ Answered November 08, 2023 at 21:37 MST

Sega Genesis: How to fix power jack on model 1 genesis

Sun, 03 Jul 2022 18:50:02 -0700

My genesis needs jacking around with my power cable

⟐ Answered July 03, 2022 at 18:50 MST

Sega Genesis: My Genesis won't turn on.

Thu, 26 Nov 2020 08:26:55 -0700

My Genesis won’t turn on, and the LED doesn’t light up, any help/ideas?

⟐ Answered November 26, 2020 at 8:26 MST

Sega Genesis: Why does my sega genesis have sound but no video?

Fri, 05 Feb 2016 20:55:19 -0700

I've used two different AV cables so far and in both cases I have gotten sound but can't get anything to pop up on the screen, no video at all. I have a sega genesis model 2. Can anyone help?

⟐ Answered February 05, 2016 at 20:55 MST

Sega Genesis: Power light briefly stays on then goes off

Tue, 26 May 2015 11:59:29 -0700

I just picked up a Sega Genesis, and I have a power adapter that I can plug into it. When I have it plugged in and the switch on the off position, then put it into the on position, the red light briefly comes on then goes off.

Is this an internal issue? Bad bulb? Bad power cable? Is that how it's suppossed to be? I don't have a video cable for it yet.

Thanks.

⟐ Answered May 26, 2015 at 11:59 MST

Sega Genesis: Model 2 wont load game, powers on to license screen then nothing

Thu, 26 Jun 2025 10:35:39 -0700

What should I check next for a model 2 not loading game past licensing screen? Voltage regulator good. The board has been looked over for corrosion and none. The power and av ports have been reflowed. The cartridge slot has been cleaned. The games being used on this system work on another system fine.

⟐ Answer accepted June 26, 2025 at 10:35 MST

Sega Genesis: Power switch replacement, is it easy?

Sat, 10 Dec 2022 13:11:08 -0700

so i have two Genesis model 1 consoles and one has a very stiff power switch and the other console doesn’t work but the power switch is very easy to slide. So I want to swap the power slide switch but I can’t find any videos about this. However, I’ve seen a photo of one that was removed but the guy that took it off said he broke it and in the photo there was a spring beside the switch. I guess I just want to know if I desolder the switch, is it going to just fall apart on me?

⟐ Answer accepted December 10, 2022 at 13:11 MST

Sega Genesis: Fried Sega Clone. Any ideas on repair?

Wed, 12 May 2021 21:43:46 -0700

Hi there.

A friend brought me a Sega Mega Drive 2 Clone. It's a lot simpler on the inside not like the original.

I plugged in my router power adapter by mistake and of course because of the higher output I heard a buzzing sound and a bad smell and now the Sega is not turning on at all. I think I fried it but I really would like to try and repair it. They're cheap like 20$ but I'm really eager to repair it myself.

Any ideas what could have died and what I could soulder maybe?

I'm providing a picture of the actual board I found online. Here's how it looks on the inside: http://hirudov.com/sega/images/ExtremeLa...

⟐ Answered May 12, 2021 at 21:43 MST

Sega Genesis: So... I found this thing in a field... in a ditch...

Sun, 13 Nov 2016 09:15:31 -0700

This thing is all kinds of screwed up. If you look at the back of it, the rf port is rusted and the only thing that moves more than a cell length is the power switch. Surprisingly, BOTH of the pieces of plastic that are always lost are still there. So, does anybody have any idea what to do first? (Other than open the case and remove the rf shield)

October 21: SO... I opened it and to no surprise at all, It was beautifully disgusting. The Shield is Rusted (NOT the beautiful silver shown in the guide), The screw under the headphone jack is black (No golden screws in the console), and I used a WHOLE freaking can of compressed air on it. And it's STILL DIRTY! (like actual dirt.) On the bright side, I did get most of the rust, dirt, and corrosion off of the motherboard. I will get around to taking a picture of that nasty "silver" piece.

⟐ Answer accepted November 13, 2016 at 9:15 MST

Sega Genesis: Help I need help!

Wed, 27 Jul 2016 18:37:34 -0700

Can you show me where is the cartridge spot

⟐ Commented July 27, 2016 at 18:37 MST

Sega Mega-CD karaoke: Recapping Mega-CD Karaoke

Wed, 09 Jul 2025 18:59:21 -0700

Hi I was wondering if you could please label the capacitor specs in your pictures. I attempted to re-cap without taking beforehand pictures and now need to recheck the work.

⟐ Answered July 09, 2025 at 18:59 MST

Sega Genesis: jumpy screen after 20 minutes already cleaned.

Wed, 21 Feb 2024 10:27:02 -0700

works fine for 20 minutes then screen starts to jump . have cleaned and its not overheating.

⟐ Answered February 21, 2024 at 10:27 MST

Sega Genesis: Why won’t the Genesis turn on?

Tue, 15 Aug 2023 10:28:14 -0700

Hello!

So this question is kind of part of a wild goose chase, but I want to learn so all answers are welcome.

Essentially, I am teaching myself to repair things. I got a Sega Genesis a couple years ago. I had a fancy cord that I could adjust the voltage and polarity on. It got the Genesis running.

To my knowledge, I never fried the console with this cord. However, I wasn’t always able to get my hands on this cable. So I tried others and I can’t power it. Makes me think I potentially fried the board, or maybe I just never found a proper substitute.

So here’s the question.

Assuming the problem is based in the motherboard, what could be the issue? The capacitors did need to be replaced but that is all I remember being an issue.

I’m learning to solder so I’m up for a challenge.

⟐ Answered August 15, 2023 at 10:28 MST

Sega Genesis: Need to find Genesis EM & EMI replacements

Mon, 07 Aug 2023 04:20:27 -0700

Hello i found out that one of my OLD SMD have been stripped by my younger brother for some electronic parts (IDK project of some kind)

So i need to replace:
EM 11
EM 12
EM 13
EM 16
possibly EM 14 also
that are located near joystick port 1
and
EM 31 near the RF box

Has anyone have a list of the EM's/ EMI's for replacement purposes?

⟐ Commented August 07, 2023 at 4:20 MST