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| Help repairing an AppleCD 300 | |
| Posted by: feeef on 2026-09-16 10:04:29 I am trying to repair an AppleCD 300 drive that is not able to to read CDs. Caddy insertion works, I hear the disc spinning, I hear it try to access the data, but the CD is ejected straight away. I recapped the main board because the old caps were licking badly. Some pads were a bit damaged but I have tested the connections of all the new caps and they were OK. Unfortunately, that didn't help. I suspected a bad lens so I put the board into a known working drive. I got the exact same result with the CD being ejected straight away. Therefore, I am pretty sure the problem comes from the main board. However, apart from the bad caps, that are now replaced, I don't see any obvious issue on that board, which seems to be in pretty good shape otherwise. Where do you think I should search?  | |
| Posted by: robin-fo on 2026-09-16 10:41:36 I have a similar issue with one of mine | |
| Posted by: feeef on 2026-09-16 11:59:28 @robin-fo, have you tried to investigate? | |
| Posted by: feeef on 2026-09-16 12:20:34 I was thinking that apart from the caps, the other thing that may have been altered with time are those potentiometers. Maybe due to dust or dirt (this drive was very dirty when I got it!). However, I don't know what they are and how they must be set, so I am very hesitant about touching them, even slightly. | |
| Posted by: Froggy814 on 2026-09-16 12:36:42 Ah yes, the pot's. You might be able to learn something from the PS2 Slim guide for adjusting them. I don't know much about that though. | |
Posted by: Froggy814 on 2026-09-16 13:33:02
How to Fix Disc Read Errors on a PlayStation 2 Slim (SCPH-70012)If your PlayStation 2 Slim (model SCPH-70012) struggles to read discs, skips during gameplay, or displays "Disc Read Error" messages, the issue is...
www.ifixit.com
Someone also made a piece of hardware for very precise calibration. | |
| Posted by: feeef on 2026-09-16 13:55:38 Thanks for the tips @Froggy814 ! In my case, the main board has 6 potentiometers and I am sure that the issue doesn't come from the lens itself. I can try to clean them by marking their position with some paint, then turning them with some contact cleaner. | |
| Posted by: Froggy814 on 2026-09-16 14:31:36 You can thank James from James Channel on youtube and his "portable" Ps2 Slim made of ducttape shell for showing me this info to pass on. But I am glad I can help! Is there a schematic anywhere to find out what each pot does? If there isn't I hope there is a semblance of markings to figure out what to turn! | |
| Posted by: pl212 on 2026-09-16 14:52:01 I've recapped 2x of these Sony drives to no avail; I think we're at the point where not only have these drives' SMD caps leaked but they've taken out the SCSI controller chip just below the 50-pin connector. The corrosion gets under this chip -- which, being also surface-mounted, has quite fragile legs. Almost all of these drives on eBay are sold as 'untested', which is a euphemism. Would love to be proven wrong if someone has a working caddy-loading drive from the IIvx/Centris era! | |
| Posted by: 4seasonphoto on 2026-09-16 15:18:33 Did you take special precautions when handling the laser pickup? There are typically a couple of PCB traces which need to be shorted with a dot of solder before you unplug the part. Failure to do so means a wrecked laser diode. | |
| Posted by: feeef on 2026-09-17 01:03:10 I tried to clean the potentiometers but that didn't help. Also, I checked the chips around the caps and there is no trace of corrosion there. The legs are all perfectly shiny and I doubt any liquid has ever gone under those chips. The main board sits upside down in its enclosure so the caps liquid doesn't stay on the board and tends to fall on the caddy, which then smells very bad when that happens. The corrosion mainly happens on the caps legs and stays there. I quickly checked for continuity when replacing the caps but I don't know where they are supposed to connect to so maybe one trace is broken where I cannot see it. Unfortunately, I haven't been able to find any schematics about this drive. I haven't disassembled the laser components, nor even touched that so far. I have just removed the main board to work on it. I do have a spare working AppleCD 300 drive, that I regularly use to listen to music when I draw on my IIfx. I swapped the boards from one drive to the other to confirm the issue is on the board itself. | |
| Posted by: Froggy814 on 2026-09-17 06:48:40 Have you tried the whole thing with a different board? Then you could rule that out as faulty as well. | |
| Posted by: iigs123 on 2026-09-17 07:19:55 I recall reading somewhere that the laser in these drives can weaken over time. If that is the case I don't believe anything can be done to save the drive. I too have tried to repair one of these drives - replaced caps, adjusted, etc - to no avail. | |
| Posted by: Froggy814 on 2026-09-17 08:04:55 If @feeef can see if the rest of the drive except for the board works then you can narrow down the problem. Otherwise if it's unfixable stuff a bluescsi into it! And make it cool! | |
| Posted by: feeef on 2026-09-18 05:47:21 As I mentioned, I tested the board on a known working drive, that I use almost daily, so I am pretty sure that the problem comes from the board. If I can make the board to work on this known working drive, it will be a good part of the work done. Then, I can focus on the rest of the drive. | |
| Posted by: Froggy814 on 2026-09-18 06:55:00 👍 | |
| Posted by: Froggy814 on 2026-09-18 06:55:47 Is there a difference between the working drives PCB and the non working drive? Like a different revision? | |
| Posted by: feeef on 2026-09-18 08:40:49 They are exactly the same drives, same boards, same year, same revision. I would like to make this board work first but I am stuck. I have not been able to find any schematics. I was wondering if someone here had any experience with this kind of problem. I guess I could compare connections between caps and chips with the working board. I now suspect a broken trace around one of the caps. Due to its position in the drive the caps liquid has only stayed right under the caps. Some of the pads were quite eaten. | |
| Posted by: Froggy814 on 2026-09-18 08:44:25 I was going to say to buzz it out as best as you can and see what is NC between the boards. | |
| Posted by: feeef on 2026-09-18 08:45:16 Yes, I guess that is my best option right now. | |
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