View Full Version : Sega Genesis won't turn on.
Xavier
06-11-2016, 09:40 PM
Sega Genesis Model 1 (VA5/VA6). Got it off ebay from someone who said it worked for 10mins then died. Power supply is good. Gets 13v from the jack to the ground of the motherboard. Was only getting 7v at the regulator input and 0v at the output, so I replaced them both (there are 2). The console still wouldn't power on. Now the voltage has dropped significantly to .34v input and 0v output at the regulators. All the fuses tested good for continuity. The diodes on the diode setting give around 5v. The board is in very good condition. I'm trying to follow the traces from the regulator back to the power jack to figure out the problem. No one else online seems to be having this much trouble. PLEASE HELP!
Xavier
06-11-2016, 10:33 PM
Turns out I have another console with the same internal setup. Didn't think I did cuz one says High Definition and the broken one does not. Seems to be an issue with the power jack. Think it's just bad cuz it's getting continuity but not voltage on both sides. Gonna try desoldering the two and swapping them to see what happens.
Xavier
06-17-2016, 06:34 AM
After a bit of side-by-side comparison I've noticed that there is no voltage getting to the diodes of the console. Voltage has to travel to the diodes before it reaches the regulator, but there is less than 1v on both sides of the diode. So somewhere it's being lost between the end of the power jack and before reaching the D1 and D3 diodes, which I've outlined with red arrows.
Here's a pic:
9485
The Genesis in the pic isn't mine but it's the same model and setup. Mine still has the pin connector on it. :)
Xavier
06-17-2016, 07:15 AM
Followed the traces all the way back to the switch and it's not making connection once turned on. Thinking it burned out. Will do testing on it.
Xavier
06-17-2016, 08:49 AM
Desoldered the switch and jumped it with a wire so it would be on as soon as I plugged the power cord in and the light came on. So the power switch went bad on the console. Guess it means I need to start looking for a new one. And no I don't plan on taking it from another Genesis. That's not how I do things.
Xavier
06-17-2016, 09:24 AM
Took the switch apart thinking it would give me an idea of how to fix it without buying a new one. Once I removed the top part that you push back and forth SOMETHING went flying all over the place. So now my switch doesn't work properly anymore. HOWEVER, I soldered it back in place just for curiosity sake and although there is no resistance when I push on it it still makes contact and powers on the console. So I'll hang onto it for now unless it gives me issues then I'll see about getting a new one, which apparently it is very hard to find a suitable candidate. But now it makes me think that there was never anything wrong with the switch itself in the first place and that maybe it was the solder. Too late now. But it works either way so still worked out.