CD Fuses

[Strider]

Do Sega CD's have fuses? If so, are they located inside the units and are they replaceable?

[nathanallan]

They do have a fuse of a sort, looks like an IC or resistor, though, so it can fool you. On my Model 1, it is near the sound outputs on the rear edge. It was burned when I got it so it needed replacing. I used an automotive rig, glass fuse with a plastic fuse holder. I thought about getting the old one out, but instead I just jumped it and left it there.

In my case, I had to use a 4A instead of the 2A, this still needs to be replaced.

So yes, it has a fuse and sometimes they need replacing.

Nathan

[Strider]

Thanks for the pic Nathan, much appreciated. So it will require some soldering?

[TmEE]

in my MCD2s, you can get away without using any soldering (but not adding any fuse) by twisting the fuse around so the legs get connected... soldering is not difficult, you just have to use additional flux

[nathanallan]

I had to, but yes if you tie the ends of the wire tight enough and get a good physical connection, no solder required, BUT the thing may break contact as it is being moved and totally turn off. That's a very annoying thing to happen. Solder highly recommended.

Nathan

[superlarz]

im kinda of electrically illiterate.. i just got a model 1 sega cd, pretty sure it is having the fuse issue (the guy i bought it from had the wrong ac adapter with it)

does anyone have a idiots guide to fuse replacing/bypassing for a model 1? if not, would anyone be willing to answer my stupid questions as they come up? thanks in advance

[17daysolderthannes]

im kinda of electrically illiterate.. i just got a model 1 sega cd, pretty sure it is having the fuse issue (the guy i bought it from had the wrong ac adapter with it)

does anyone have a idiots guide to fuse replacing/bypassing for a model 1? if not, would anyone be willing to answer my stupid questions as they come up? thanks in advance

make sure first that the power supply wasn't too LOW rather than too high. Most non-official power supplies (the original was 9V 1.2A) have too LOW of an amperage rating to fully power the Sega CD, so it will boot and not play games or may not boot at all. If you have the official supply and it still doesn't work, its probably a fuse issue. The best way to find out is to grab a multimeter and poke around until you find one that reads in the mega ohms or greater (a working fuse should read near zero ohms in most cases).

[TmEE]

There is no such thing as too high supply, a device takes as much it needs, and anything over is left there... if there's too little, the device sucks as much as it can and due to excess power coming through the supply, it will get hot and will start burning if its weak enough in the latter case.

[superlarz]

The adapter it came with doesnt supply enough power. i tried to hook it up with the official sega ac adapter (the same adapter used by the model 1 genesis) and got nothing, which leads me to believe it is the fuse..

[nathanallan]

test both supplies with a multimeter if you can, make sure they both work (unless you know they are good with another console).

Fixing that fuse was one of the easiest jobs I've had on a console. Oopen it, locate the fuse, jump it with another replaceable fuse. Soldering rules apply, don't drip, don't make a blob, etc.

There is no such thing as too high supply, a device takes as much it needs, and anything over is left there... if there's too little, the device sucks as much as it can and due to excess power coming through the supply, it will get hot and will start burning if its weak enough in the latter case.

Right, but this is for amperage. You can't use the 30vdc with 3A rating, that will be bad. If there are too many Amps, you'll be okay. Match the voltage the best you can (like he said before, 9-~15vdc, tip negative, <1.2A. I dunno, somebody said that somewhere I think.

Nathan

[superlarz]

the power supply the sega cd came with is clearly labeled, and does not match SCDs needs. I tried the unit with my other SCD AC adapter and got nothing out of it.

[nathanallan]

I see, you can test the fuse before you go soldering anything, see if a current will pass through with a multimeter (look for ground, makes a beep or gives a reading on the MM)

[17daysolderthannes]

There is no such thing as too high supply, a device takes as much it needs, and anything over is left there... if there's too little, the device sucks as much as it can and due to excess power coming through the supply, it will get hot and will start burning if its weak enough in the latter case.

Right, but this is for amperage. You can't use the 30vdc with 3A rating, that will be bad. If there are too many Amps, you'll be okay. Match the voltage the best you can (like he said before, 9-~15vdc, tip negative, <1.2A. I dunno, somebody said that somewhere I think.

Nathan

Actually, you're both a little wrong. Too high of an Amperage will certainly cause it to fry, but in this case we're talking like 10A or something. As for voltage, too high of a voltage could also damage it via arcing (though, again, that's for really high stuff, tasers for example use several thousand volts and we all know how those puppies work). I think the biggest problem with a too high voltage supply would be the extra heat brought into the system that would wear out the voltage regulator or cause other problems. For these applications, however, you have quite a bit of range, for example, I have a portable CD player that works from 7.2V~12V (that's the rating on the bottom, you could probably go higher if you wanted) and has a pretty beastly 2.2A A/C adapter. I just fixed it last night too, wasn't reading DVDs or CDs, but I showed it who's boss (it was a combination of a crooked ribbon cable and laser potentiometers too high).

[Strider]

Nathan,

What are the chances of you posting up some close-ups of the wiring? I have my CD apart but from the angle of the picture you provided it's tough to see where the wires are soldered.

Thanks!

[nathanallan]

Chances are good, but I have to get at my tools in the shop tomorrow-- me without a screwdriver, what a world! I'll open her back up tomorrow and take more pictures.

But even without pics, it's really easy, you look on that corner of the mainboard, find F1 and you'll see exactly where to attach the new fuse.

Nathan