Hi. I managed to get a SCPH 1002 console a couple of days ago but unfortunately it has issues. The console turns on and displays BIOS just fine (controllers and memorycards are working). But when I insert a CD (Both PS1 game (original) or Audio) the disc doesn't spin. I pressed the "lid closed" switch and I can see the laser lights on and jumps twice but as I sad discs are no go. While searching for a solution I stumbled upon a guide for laser adjusting and I used a multimeter to check voltage on test points. Laser intensity checks out fine (11.4 mV) and so is bias (1.70 V in idle mode), but when disc should be spun the voltage jumps to 2.0 V (it should be 1.82 by the guide). Messing with the gain gave no results. Has anyone had this problem and if it was solved how did you do it? My guess is that trimmer is probably messed up but I would like to be sure before I decide to replace it.
Possibilities off the top of my head: Laser lens is dirty. Wrong laser installed (possible but I'm not 100% sure what sort of symptoms you'd be seeing) Motor is shot. Ribbon to laser assembly is partially functional. I'd suggest swapping in another laser assembly and seeing what happens. Beyond that I can't think of what the issue is off hand for sure as IIRC Playstations typically spin the disc as soon as the thing is turned on. Laser recognition of the disc is either not requisite or comes after the spin up has been performed. Based entirely on empirical observations and not electronic measurements.
If you can't lower the GAIN then you will need to remove the POT and install some resistors to give you 0.12 V - 0.15 V. I will try to get you the correct values for the resistors, last time I did this was 8 years ago. Cleaning or swapping the Laser will do no good in this case
Let us know what you find! I've got a SCPH-1000 that seems to have the same issue so I'm interested in what you will find. I know I need a new laser for my unit regardless because I accidentally tore the cable, but it seemed to tear really easily, so that might have been the issue to begin with but I don't have a spare laser unit at the moment. Regardless though my SCPH-1000 was showing the exact same symptoms. -Disjaukifa
I would try to reflow soldering the CD-ROM portion of the board. Mainly the CD-ROM interface chip (CXD-1199), the CD DSP chip (CXD-2510) and the mechacon chip (which is on the under side of the board, close to the DSP chip).
I have a SCPH-500o (or 5500) unit i bought as junk which has the same issues. I would guess its the motor If anybody knows, speak out!
@APE: I cleaned the lens so that's not the issue. Per your suggestion I also swapped laser units between 1002 and 9002 (was a bit hard due to different cable lengths) and the laser from the 1002 unit works fine in 9002 (spins the CD) while the one from 9002 in 1002 behaves the same (aka not working). @jinn: Yeah I think that could be the issue. Is there a possibility that a fuse can be blown also? Update: Well I fiddled with the gain pot and after 15-20 turns to one side it became responsive. So I set everything to correct values and now CDs are spinning. Audio CDs play out fine but games are unable to start... The strange thing is that the console doesn't spin the spindle twice if there is no disc as the other PS1s i own do.
Wow, it has been a while. Anyway I dug through my stuff and found this PS1 so I wanted to give it another shot. Is seems like only 1x speed is working but not 2x. When the game is placed on the spindle it will slowly start to spin it but the PS1 never boots it. I checked all the fuses I could see but all are ok.
I just gave away a unit like that, unplug the spindle motor, put a cd in the unit and probe the spindle motor pins. You should get a measurement of about 4.53V, Also probe the motor it should read 11Ω. Bad motors are rather common, they usually read about 11.5Ω when they die. Both failures screw up the rotation speed, audio CDs are quite tolerant of this problem but game CDs will struggle to run in 2x mode and in a late stage failure the system will give up before reaching 2x speed. I do not know how to fix the issue though.
