Help troubleshooting CDROM2

[Chrom_]

I'm seeking for some ideas on how to repair my NEC CDROM2. When I first got it, testing it as a CD player with no briefcase attached, I would only get a 0 displayed on the LCD, but no movement. I have changed the middle gear and greased the spindle. Now the CDROM laser moves correctly and I can hear it focusing, but the CD won't spin.

My ideas are:
- possible PSU not delivering enough power (I'm using an universal PSU)
- broken laser block (how to check for this?)
- needed potentiometers adjusting

Any ideas on how to troubleshoot it?

Thanks a lot for any help

[Vimtoman]

Have a look at TG/PCE Repair/Mod Discussion on the main page.
It has all the info you need.

[choijimmy]

I'm seeking for some ideas on how to repair my NEC CDROM2. When I first got it, testing it as a CD player with no briefcase attached, I would only get a 0 displayed on the LCD, but no movement. I have changed the middle gear and greased the spindle. Now the CDROM laser moves correctly and I can hear it focusing, but the CD won't spin.

My ideas are:
- possible PSU not delivering enough power (I'm using an universal PSU)
- broken laser block (how to check for this?)
- needed potentiometers adjusting

Any ideas on how to troubleshoot it?

Thanks a lot for any help

Try to replace some 4.7uf/3.3uf capacitors first to see it helps or not. I encountered few cdrom units with bad capacitors.

[Chrom_]

I've changed PSU and the problem is the same. I'm suspecting that the spindle motor is gone. Ive done a "soft" test by applying voltage form a battery directly to the spindle motor leads and there's no movement, so I've ordered a replacement motor just in case (waiting for it to be delivered at the moment)

I've also checked the spindle sensor that is activated by the laser block. The sensor is in working order (goes from 1k ohm to 0 ohm when the switch is pressed). Also manually pressing the sensor switch doesn't produce any spindle movement

The caps look fine but of course they're quite old. I'll try recapping for the motor swap doesn't make effect

Any other idea is very welcome

Thanks

[blueraven]

I've changed PSU and the problem is the same. I'm suspecting that the spindle motor is gone. Ive done a "soft" test by applying voltage form a battery directly to the spindle motor leads and there's no movement, so I've ordered a replacement motor just in case (waiting for it to be delivered at the moment)

I've only seen one motor go bad. Check it with a 9v battery. if it spins, its working.

I've also checked the spindle sensor that is activated by the laser block. The sensor is in working order (goes from 1k ohm to 0 ohm when the switch is pressed). Also manually pressing the sensor switch doesn't produce any spindle movement.

You're overthinking it a bit. Have you tested the unit with a briefcase at all? I've had CDROM2's act wierd as standalones.

The caps look fine but of course they're quite old. I'll try recapping for the motor swap doesn't make effect

I would start with a recap, after testing in an IFU.

...and as vimtoman says, all of the info you need will be on the repair forums. if you cant find what your looking for in recent threads, go to the search function and type  troubleshooting CDROM2.

Good luck.

[Chrom_]

After some more troubleshooting, I've found that the spindle motor is OK but I have found that one of the ribbon cables was inverted (go figure). After plugging from the correct side, the laser beam comes up. I managed to read some audio CD, though the drive struggles a lot. Next I'll recap the whole unit and check if it fixes the problem, otherwise I'll check the pots

[Chrom_]

For future reference to anyone following this thread, I've reached the final stage of fixing my Cdrom2 today by full recapping it and fixing a broken trace on the pcb. At this point the CD-ROM was already able to read audio CDs but skipping tracks even if very gently tapped on the case, so I have also tweaked the pots and it is finally nice and stable

[blueraven]

Well done. Glad to hear that you got it figured out.