need some advice about repairing a PC Engine Cd Rom2

snintendog · 05/24/2016, 12:41 AM

I had gotten one fairly cheap with a IFU a while ago the last person seemed to have tried to fix it I had gotten the laser to move correctly and the disk to spin but i can't seem to find the reason it just gives up trying to read it outside of replacing the laser itself.

The IFU is confirmed to work the ribbon cables and board are in good condition, the grounding wire seems to be properly attached to the large ribbon cable to the ground the magnet is still in place. (might just replace that with a clip due to my test disks getting scuffed every now and again)

I noticed that the lasers seem to be getting harder to find lately i only found one for 154 on ebay and salvaging from the walkman listed in the sticky is there any other known source for the laser or are they just drying up?

MNKyDeth · 05/24/2016, 07:55 AM

On eBay search for hop-m3. A bunch should pop up for you. Assuming the ifu's also use hop-m3's I am not sure as I never had one.

If the caps have not been replaced this is where I would start first though. I am not very familiar with the ifu's, but unless anyone else says otherwise replace all the caps before playing with other components so you know you are on a solid base of a machine first.

After caps and a new lens it's all finding any bad traces and adjusting the pots. Again, assuming the ifu's have these features, issues.

Ergot_Cholera · 05/24/2016, 09:22 AM

CD-ROM² use KSS-220A or KSS-162A laser. I agree that replacing the caps is a good idea, the 4.7uF caps near the volume dial tend to have leaked in my experience.

choijimmy · 05/24/2016, 10:17 AM

Yes, replace those 4.7uf caps will help. I have couples cdroms are fixed by replacing all 4.7uf cap.

snintendog · 05/24/2016, 05:41 PM

Ah thanks will order the 4.7uF caps the board hasn't been recapped yet thank ya and i was afraid that only the Kss-220a and 162a were the only ones compatible with the Rom2 oh well gonna have to hunt for those still.

pas7680 · 05/30/2016, 09:27 PM

and finally check that the pots are correct, virtually every cd rom 2 i've had that has been opened before has had the pots messed with.

thesteve · 05/30/2016, 10:36 PM

note the pots are laser specific so when swapping lasers they will need adjustment

snintendog · 06/02/2016, 06:09 PM

Quote from: pas7680 on 05/30/2016, 09:27 PMand finally check that the pots are correct, virtually every cd rom 2 i've had that has been opened before has had the pots messed with.

You have any documentation on the pots? I have seen the duo's around but not the cdrom2's.

atman · 06/04/2016, 04:29 PM

Would 50v 4,7uF work well? Belive the original are 16v.

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choijimmy · 06/04/2016, 09:58 PM

Quote from: atman on 06/04/2016, 04:29 PMWould 50v 4,7uF work well? Belive the original are 16v.

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50v 4.7uf will work. As long as the replacement cap has same uf, equal or higher voltage is fine.

atman · 06/08/2016, 02:57 AM

Thanks for the reply, as i thought.

If the standard-values are 16V 4,7uf. Can I change the caps with 4,7 25V AND 50V?

Can I use both in the same unit? The voltage value are only for how much the cap can take, not a value that it will release..

Keith Courage · 06/08/2016, 07:26 AM

Any higher voltage is fine as long as the 4.7uf rating stays the same. You just cannot use lower voltage.

atman · 06/08/2016, 07:52 AM

Great, thanks.

Changed all the 4.7uf ones and three was bad. I could nog get a valid reading on them or they showed 0.1 uf or something.

The unit played music cds decent but went crazy in the IFU.
Hope it will work better now.