Sega CD Model 1 brought back from the dead but has a small issue.

Hello everyone! So I recently won my first eBay auction on an untested Sega CD (Mega CD) Model 1. It did not include the power supply but it did include the mounting plate and screw. In order to use it, I had to take one of my generic 9V 1A power supplies, reverse the polarity, use that on my modded Genesis Model 1 VA6, and then use my official Sega power supply on my Sega CD. After everything was hooked up, the Sega CD flashed the ACCESS led for a split second and then did nothing. I replaced the fuse and installed a automotive fuse holder so replacing the fuse will be easy in the future. After it was put back together, it turned on and was working smoothly until I tried to eject the tray. The drive belt needed replacing so I got a new one and replaced it. It works fine now except for one small problem: the green READY led never comes on. Is the led dead and if so, how do I replace it and what is power rating of the led? Also, any led color suggestions or should I stick with a green one? Any and all help would be highly appreciated!

 

There's nothing particluar about the LED in the Mega CD repair doc.

On the parts list there's only this:
38.00 LD1 117 390-5366 LED GL5PR44 RED
39.00 LD2 118 390-5367 LED GL5KG44 Green

There're feed by VCC2(which should be +5v), Red have a 360ohms resistor (R4) and Green have a 160ohms resitsor (R5).

 

Could the 160ohms resistor for the green LED be blown or is the LED itself dead? The Red LED works fine.

 

Both LED are getting there VCC2 from the same source then both of them are going to PIN 64 and 65 of the 315-5548 (IC2)


So it's the LD (more likely I would say), the resistor R5, the transistor TR1 or the resistor R7 (4.7K)

Here's the parts list for the transistor
9.00 TR1 105 482-5126 XSRT 2SC1623 L5..7 CHIP
10.00 TR2 105 482-5126 XSRT 2SC1623 L5..7 CHIP

 

All this aside, nice one on reviving a venerable Mega CD. That's some TLC right there

 

Ok, next time I have it open, I'll replace the LED and see if that solves it. How hard is it to replace and do you have any suggestions on what color I should use?

Thank you! My father helped with the soldering since I'm new to it. I got a good deal on it and yet another Sega CD was saved from getting thrown out! I can make it better though. I plan on installing a region-free Japanese Mega CD 1 BIOS chip in it once I get the parts needed for that mod. I just wonder how many more years until it stops working properly again.

 

I really should teach myself how to solder so I can handle it myself. I've never done it before, how tricky was it to get the hang of? How would you recommend teaching yourself without spending too much money?

 

The soldering iron I use is a cheap $40 soldering iron from RadioShack. There are plenty of tutorials on YouTube and you could buy some cheap wires and some cheap strip board to solder to.

 

I forgot to mention something at the beginning of the thread. The Sega CD's internal save memory auto-deletes itself after the power is shut off and needs reformatting every time. How can I fix this?

 

Need a ml2032 battery rechargeable coin cell t25 3 pin.
i full recommend fit new 10uf 16v smd caps the silver can ones with new ones since they are allways leaking a but like the game gears.

 

Ok, so I need a ML2032 and not a CR2032 right? I've heard that CR2032 batteries cause damage to the system. If it still has problems, I'll replace all of the caps, and if it still doesn't save after that, then I'll just get one of those Ultra Back-Up RAM Carts and call it a day.

 

ML2032 is a rechargeable battery. CR2032 is not. Putting a CR2032 in you MegaCD could damage the system indeed.
There's a lot of ML2032 with holders on ebay.

For your LED, any standard LED would work (it's a 5mm or 3mm diameter).

 

Ok and thank you. I'll get the parts as soon as I can and hopefully everything will work like it just came off of the assembly line. I was wondering about save games too. If I had a region-free BIOS installed and I made a save with a USA copy of Sonic CD, would the Japanese/PAL copies use that save or would I need a separate save for the different regions?

 

Bumping because nobody has answered my question about Sonic CD saves yet and a miracle(?) just happened.

The green "READY" LED just started working on its own. I haven't even opened it up since I replaced the belt.

I was letting the thing run for about an hour or two with the Sonic CD title screen and demos running for background noise. It all of the sudden just turned on. I don't know why but it is now working.

The battery, however, is a different story. The thing needs formatting every time I turn it on. Once I start up Sonic CD, the game says the internal memory is full. It apparently fills itself up with 45801 used out of 125 memory and then deletes both the save memory AND the formatting upon shutdown. I will replace it.

 

People already told you how to fix the backup ram problem. Without power it will erase or corrupt.

That's what is happening with your unit. It simply spent many many years without use and the battery died because of that.

 

Once again I typed without typing what I was thinking. I remember people mentioning the battery replacement and that's what I have been planning on doing. I was explaining what happens when I reformat the memory. Sorry for any confusion.

 

Just mentioning, I have a 1991 Model 1 Japanese MEGA-CD (similar to your SEGA-CD) which still saves fine with the original battery.

I always keep it charged. Perhaps that's why it's original battery is still working. lol

 

lol the original owner of mine must have taken poor care of it then. The AVGN was wrong about the Sega CD/Mega CD, it's an awesome add-on that is still fun to use today.

 

AVGN is an idiot. We watch him because watching idiots can be fun.

 

AVGN only complained about the lacking library, and load times - along with the setup.