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Released December 3, 1994 in Japan and September 9, 1995 in North America. Models SCPH-100x, SCPH-3000, SCPH-3500, SCPH-500x, SCPH-550x, SCPH-700x, SCPH-750x, and SCPH-900x.

Possible causes for disc not being read

Hello fellow repair enthusiasts

I recently bought and fixed a PS1 SCPH-1002 but it does not seem to want to read neither PS1 discs nor CDs.

Can this be caused by me replacing the spindle in the middle that holds the disc in place over the laser?

If so, is there a standard distance between the laser and the disc?

Thanks in advance for any input or information

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Hi!

Could be a lot of things...

Could be the laser that is bad and just need to be replaced!

Could also be the sensor on the motherboard that is defective and need to be replaced.

Could also be caused by a bad modchip..

If the PS1 is modded, then please remove the modchip and try again. This would be the first step,

Otherwise, replace the laser and see if that works!

Please keep us posted!

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The PS1 is not modded. I've opened it up and no loose flex connectors or other connectors. The only thing I can think of is the 1mm(0.04 in) gap between the laser and disc itself not being that distance as it seems to go into "bios" and work otherwise.

After a lot of diagnostic tests I've found that it does read CDs if turned on its head

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Okay, to save you a lot of trouble, I would just replace the laser deck completely. So, replacing the laser, spindle and all other small parts. It's not that expensive and will save you from a lot of headache! IF, you don't want this and replace the small parts, then replace the spindle, this will most likely fix it. I'm not sure where you can buy that one, but it should do the job. Maybe eBay or Aliexpress!

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I will give reseating the spindle a try. I have a feeler gauge at home due to my 3D printing hobby and 1mm should be the required spacing

If you are looking for it yourself one day

You can find it here:

https://www.zedlabz.com/products/zedlabz...

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Ah great! Thanks for sharing the link! Please let us know how it goes with the spindle :)! If you need any more help, please let us know!

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Seems the laser is a Ksm-440 ACM

Not a KSM-440BAM which as far as I'm aware needs less resistance in the laser potentiometer. Any thoughts?

Before I started tinkering it was set to 1210 Ω. Best for the Ksm-440 ACM is as far as I've heard around 1kΩ or thereabouts

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Hie there! Just a few tips and some solutions you could use.

If the disc isn’t held firmly by the spindle and clamp, it may wobble, causing tracking and reading errors.

If the replaced spindle hub sits even a fraction of a millimeter too high or too low, the laser won’t be able to focus on the disc surface.

Try this!

double check that the spindle hub is seated fully and evenly, try to clean the laser lens with clean cotton cloth.

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I've tried this. The only "non standard think is 1.21kΩ setting on a 1k preferred laser

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Markus Norstrøm crwdns2934231:0crwdne2934231:0
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