Sega CD systems repair thread

[jSpydur]

If it shows just the background and nothing else, including sound, the most common problem is the connector on the MD. Try giving it a clean and see if that helps. Cleaning the contacts on the CD side could also help.

This is the exact problem I have been having, I took it apart and cleaned everything, then resat the ribbons but it is still freezing on the startup screen. Do you have any other advice?

[qzack]

Hello,

I just read through this entire thread looking for my problem with my Sega CD Model 1 and didn't see it. I will reference this thread for any issues that come up but here is my problem.

I have a Sega CD Model 1 USA with a Model one Genesis. I found this problem by trying to play Sonic CD when I bought the unit off Ebay. The seller didn't list this as a problem but unless you have a game that saves to memory you wouldn't know if the unit has a problem or not. I put the Sonic CD disc in the drive and it starts to boot and I'm greeted with a "You must format the system memory before playing this game" or something to that effect. I boot the Sega CD up with no disc, press start, select option and choose the option to format the memory. I am greeted by an error message that says "Cannot format system memory" followed by a negative sounding beep.

I have read on one other forum that this issue could be caused by power as the Sega CD will lock the Ram to battery power if the voltage is not proper or high enough. One person said that they had this issue when they tried to replace the voltage regulators and didn't use the proper one. To try and troubleshoot this I have purchased official sega ac adapters and it didn't correct the format issue and I have also replaced the system battery which also gave no results.

I have a cap kit on order, will that fix this issue..? Another person I chatted with thought I should replace the Ram but I can't even access it. If I could access the ram, format it and see that it was messed up it might explain that I need to replace them. I'm leaning more on a voltage problem. The system plays fine otherwise. No sound issues, audio issues or loading issues and the video is crisp and clean as I'm running it over a scart cable with a HDMI converter box.

Thanks for any thoughts or advice on what could cause this issue.
I will be happy to post the fix as it is not posted in this thread as of yet so it must be a rare issue and I'm lucky enough to have it.

[qzack]

This is the exact problem I have been having, I took it apart and cleaned everything, then resat the ribbons but it is still freezing on the startup screen. Do you have any other advice?

I have a Sega CD Model 1 that I just bought on Ebay and it does this every-time it's powered on.

After swapping parts around and messing around with it for much of this past weekend the problem lies in the connector board where the battery is. I have put this board into my working system and it froze on boot. I put my original board back into my system or the defective system and it boots fine. I have replaced all the caps on this board except the two 100uf ones and it didn't make a difference. It still locks up.
I've listed the unit back on ebay and will focus my attention on my working unit with the ram issue that I posted earlier.

Another person on this thread said it may have something to do with the audio acsii chip. Other than what I've tried I'm not sure of the problem.

[qzack]

I found this on another forum. I have not tried this out on mine and it makes little sense to me but when you have tried everything, what can this hurt.

http://www.fixya.com/support/t9183311-mega_cd_ii_mega

[SegaSonic91]

That sounds very.... weird! The shielding isn't even needed in the systems, Jp systems do not have them at all.

[qzack]

Same here and that's why I said take it with a grain of salt.
It makes no sense why the system would suddenly boot with the ground shielding removed.
In trying to fix the freezing issue on one of my model 1's this is not the first thing I would think about trying.

Unless by some act of god type of thing where the shielding causes a dead short, or something to that effect..?
I don't know....

My issue on my model one is on the CPU board. Whatever is wrong with it lies in there. I have swapped parts and that board even locks up my good working system.

[jSpydur]

I found this on another forum. I have not tried this out on mine and it makes little sense to me but when you have tried everything, what can this hurt.

http://www.fixya.com/support/t9183311-mega_cd_ii_mega

I went ahead and tried it haha and yeah still locks up. I just dont get how it works fine then bam, freezes on loadup. Thanks anyway for the help

[qzack]

This may or may not help with the unit freezing as soon as it gets turned on. I am at work and just read this thread over my lunch hour and it makes sense to me.
If I can't sell the one model 1 I just bought from ebay with this issue, I may keep it and try to fix it. I like the challenge of trying to learn how to fix something and gain knowledge from it.
I know this doesn't fix my ram issue but my board could very well have "trace" damage done to it from leaky caps.

The other thing is, this is not an easy fix and will require time to sort out your particular issue.

Here is a link to the thread.

http://www.assemblergames.com/forums...-problem/page2

Good luck in your efforts.

[Sights]

You Don't Learn That Every Day...

[jSpydur]

This may or may not help with the unit freezing as soon as it gets turned on. I am at work and just read this thread over my lunch hour and it makes sense to me.
If I can't sell the one model 1 I just bought from ebay with this issue, I may keep it and try to fix it. I like the challenge of trying to learn how to fix something and gain knowledge from it.
I know this doesn't fix my ram issue but my board could very well have "trace" damage done to it from leaky caps.

The other thing is, this is not an easy fix and will require time to sort out your particular issue.



Here is a link to the thread.

http://www.assemblergames.com/forums...-problem/page2

Good luck in your efforts.

Thanks for all the help, unfortunately this is alittle beyond my abilities I'm afraid. I would love to hear if you end up fixing yours though since it sounds like it may be the same problem.

[qzack]

I never did fix mine. I have enough knowledge in electronics to check for basic problems but I don't own any professional equipment as I just do this as a side hobby.
I have read a lot of forums where people have had this same problem. You turn on the unit and it freezes immediately. Some say they can hear music, others not. The one thing I do know from reading is very few have actually fixed the problem.

In the link I posted earlier I understand the process that makes the boot routine work but after checking over my board with a magnifying glass I can't for the life of me locate anything damaged. If I had to take a guess I would put it on the bios chip or something in the IC of the CPU.

I have since purchased another sega cd model 1 off ebay. This seller reports issues with the tray not opening. I plan to get the unit next week and test things out and fix this issue. In reading about this problem it leads to a belt issue. I also have another sega cd drive on hand that I have been unable to test because my earlier unit never booted properly. I will test this drive out and sell it for parts if it works. I'll also have a couple more grounding plates as well.

[qzack]

I got the sega cd model 1 that I purchased off ebay and the seller reports that the tray was stuck. Well, after I took this thing apart I discovered that the feet on the sides of the drive itself (the one where you drop the screws down in the hole to secure the drive) were broken off completely. Only one of these posts remained. I'm not sure if you can run the drive as the spinning of the disc itself would cause the drive to become unbalanced and cause massive reading errors.

I also discovered what appears to be rust that was covering a good section of the power board. Is it common to have rust inside of these units..? I can only think that this was stored or used in a damp area as my first unit did not have any rust inside of it at all.

I took the main board out of this unit and put it into my good unit and it boots up no problem and I am now able to access the ram. So I was able to play Sonic CD last night finally...

I plan on testing out some spare drives that I have for the model 1 and if they work I will sell them on ebay. I also have a couple grounding plates for the model 1 genesis a sega cd model 1 faceplate and two pairs of ribbon cables. One pair of each cable, one for the main board and one for the cd drive. The power boards out of all these units were in very bad shape and shot, so I couldn't salvage them to sell.

[omp]

My thoughts were if i couldn't repair the tray in my sega cd, but it worked, i would make my own version of the aiwa mega cd player.

[SegaSonic91]

Do you mean you will have an entire CD drive/board to sell? I would be very interested in one of them along with the ribbon cables. How much will you be after for them? Hell, if I could afford it, I'd probably be interested in more than one if they are in working order. Do you know if they are Sony or JVC units?

Rust is always common on MDs around the modem port but I have never seen a rusty MEGA or SEGA CD

[qzack]

Do you mean you will have an entire CD drive/board to sell? I would be very interested in one of them along with the ribbon cables. How much will you be after for them? Hell, if I could afford it, I'd probably be interested in more than one if they are in working order. Do you know if they are Sony or JVC units?

Rust is always common on MDs around the modem port but I have never seen a rusty MEGA or SEGA CD

Yes!!! I believe it is a Sony Drive. I am at work at the moment so I cannot check. The drive works but has the "Grinding" Gear problem. I hooked it up to a working Model 1 that I have, popped a game in and it read fine without issues. The noise happens when the laser is in seek mode, probably when its going back and forth to read tracks on the disc. The noise did not affect gameplay when I tested the drive. The tray ejects and works fine. It would be a perfect drive but the grinding noise is what ruins it.

I also have another drive that when I received it the person I bought the unit from broke off the legs that the drive sits on inside of the model 1. Does that make sense...? So the drive is unbalanced as it has nothing to sit on but I'm sure someone could use parts off of it. I can post some pics when I get home from work tonight if your interested. Let me know....

I have two sets of working drive ribbon cables. In two sets I mean one for the main board and one for the power board. So there would be four cables altogether. I also have the grounding bars that the cables slide through as well. One for each cable.

I also have two sets of genesis model one grounding plates with screws and the small piece that attaches to the bottom of the genesis itself.

Finally have one more part, a genesis model 1 connector. The connector block used to connect the sega cd model 1 to the model 1 genesis. I tested it on my working unit and it works fine.

The one CD Drive, Ribbon Cables, Genesis Connector & Grounding plates can be found on ebay here:

http://www.ebay.com/sch/i.html?_saca...odel+1&_sop=10

I have 100% positive feedback (when people leave me it). My feedback score should be a lot higher but it seems people are lazy and don't want to leave it. Personally I could care less but it would be nice to have my numbers go up after I buy 20 plus items off Ebay instead of staying the same. My Ebay seller name is the same as my username on the forum.
I have the auctions listed as 7 days and just listed everything last night.

I appreciate the interest as this stuff is useless to me as I have finally go a model 1 that works perfectly but it costed me more than I wanted to spend. So I hope to make a few bucks back with these parts if I can.