The All Aussie Sega CD Model 1 Repair Adventure

G'Day everyone, I am currently doing a Sega cd model 1 repair project and I wanted to share my experience in case I can help others or others could help me. This is for educational purposes only and I'm not responsible for any issues that may be caused by following this guide.....blah...blah

The following issues have been repaired so far:
Darlington Transistor
Fuse
SMD Caps and all other Caps
Drive Unit (including new belt and helix screw)
Laser and Laser Chip (CXD2500AQ)

A big thank you to the following who have helped this project

Dan
http://www.gumtree.com.au/s-ad/coom...ification-repair-and-refurbishment/1111521561

Darren Cox
https://www.retrosales.com.au/
http://www.globalgarage.com.au/
https://www.youtube.com/user/GlobalGarageAus

Nerds Warehouse
http://www.nerdswarehouse.com.au/

@Shane McRetro
@omp
@bart_simpson
@l_oliveira
@Druid II


Watch this space....

 

Issue 1

No Power (as common as mud)

The fuse was taken out and both points were soldered together and the Darlington transistor blew (due to wrong power supply)




Replaced with new fuse and replaced transistor. I used a 2.5 amp fuse, I know it should be 1.5 amps but I have read that this is still in tolerance.

Big shout out to my mate Dan for helping me out with this step!

 

Issue 2

Will not turn on.

After troubleshooting for a couple of days, it turns out the pins in the Genesis cartridge slot were touching and preventing the Sega CD from booting up (I'm guessing it creates a short) Re-aligned pins and now starts.

 

Issue 3

PSU to Motherboard Ribbon damaged. It still works but I've ordered a replacement from Ali-express

The ribbon is 21 pin, 1.25 pitch, 27mm wide and 85mm long, Type A

Ordering Link: http://www.aliexpress.com/item/Ffc-1-25-21p-20-core-85mm/883472933.html

 

Issue 4

Replace all smd caps with electrolyte capacitors. Some had started to leak and held no charge. Thanks again Dan!
.

 

Dump that EPROM for us, pretty please, with a cherry on top.

 

Hey I_oliveira, I would be happy to give it a go, I have no idea what to do though. Is there a guide you could point me to?

 

x

 

Besides send it to someone with a chip reader you can use Retrodev Transfer (http://www.retrodev.com/transfer.html) and a CD bios dumper app. All you need is a PC with LPT port and a custom manufactured cable.

 

Hi Druid II, I have contacted Shane McRetro and he will help me with the dumping. I have a sega cd 2 on the way and when that arrives I will remove the chip and send it to him. Happy to help the community

 

Hi I_oliveria, thanks for the suggestion, I will send to down to Shane McRetro when my model 2 arrives. Thank you

 

x

 

Hello everyone, happy to help dump the chip.
I've just beamed my postal details over to @Brad_83.
For helping out I've offered a free 27C1024 with his choice of code.
If anyone wants to throw some suggestions as to the best of the best code, go bananas!

 

Issue 4

Tray not raising completely when door is closed.

Removed tray and discovered tooth missing on worm gear..... Bugger...... I've heard of this before.



Fix 1 - JB plastic weld, mould a tooth and let cure. FAIL- tooth disintegrates

Fix 2 - Remove missing tooth completely, replace with small precession screwdriver. FAIL - still skips a tooth

So I decide to research part replacements and I found the product code for the mechanism thanks to bart_simpson from http://assemblergames.com/l/threads/sega-cd-finally-repaired-sort-of-what-to-do.42703/

The part is a KSL 2101ABM.

So I dug a little deeper and found the service manual from a NAD 512 which uses the same mechanism and found the complete list of parts and diagrams of the unit. I have included this as a download.

The part I need is 2-626-005-(03) CAM (G), Control. I have started to ask around for the part, I don't like my chances however as Sony stops making parts seven years after the systems ceases being made (If anyone has a spare they could sell that would be fantastic)

I decided to take a chance on purchasing a whole unit from yoycart, hopefully it turns out ok

http://www.yoycart.com/Product/528292998355/

Watch this space

 

Hi @l_oliveira,

A huge thank you to @Shane McRetro for dumping the bios and he has confirmed that it matches the existing bios byte for byte.
The bios can be found here: https://drive.google.com/open?id=0B3Rk2eO8E26vRjV1eU9wZXNxQXM Is there a place where this should be linked or moved to on the forums?

Shane has kindly offered to give me a bios of my choice, I will be using the Japanese Region-Free bios that you created located at http://assemblergames.com/l/threads/mega-cd-real-region-free-on-game-discs.27562/ The link appears to be down but it can be downloaded at http://www.mmmonkey.co.uk/console/sega/megacd-regionfree.htm

Thank you everyone

 

These units at Yoycart are back in stock in case people are interested

 

I'll pick one up, why not right? Cheap as can be!
This line during the checkout sure is interesting "EMS can deliver liquid, powder and some counterfeit products."

 

Yeah, I wonder what "some" refers too.....

 

Did you receive it? It comes without the optics,right?

 

Hi beharius, I haven't received it yet, it doesn't come with the optics, just the tray mechanism.