Help troubleshoot PS2 slim with Modbo4 , GH-040-02

Hiya!

I installed a modbo4 in a friend's PS2 slim but I can't get the damn thing to read PS2 disks. I get the Matrix Infinity logo on boot, I can access the modchip's boot menu and save settings. When I put a PS2 disc (backup) sometimes I get the ps2 boot logo (patched with matrix logo) , then a blank screen and then a message saying "unable to read disc". Other times in browser it reads and drops me to the media screen, the PS2 disc is recognized there but if I run it I get the black screen treatment , then it's either "unable to read disc" or back to media screen but now the disc is a DVD Video one.

Maybe I have some point wrong? Here is a pic of my installation:



I followed this guide:



... with the alternative BIOS points from this pic since I find it easier to solder and used them numerous times in the past when available (checked them for connectivity - they are correct)



Can anyone spot anything wrong? Any advice will be greatly appreciated, thanks!!!!

 

Do your original PS2 discs work? What media are u burning your backups to and what speed?

 

Well, as-is original discs do the same. It boots CDs fine though , DVDs give it that error.
The backups I use to test are DVD-R burned on Ritek G-04 media, they are old , scratch free and work fine.
I forgot to mention that I did try with another laser from another slim (I can't be sure the new laser is not dead though - the donor ps2 does not power on) and I get the same result in my testing. That's why I am thinking maybe it's an installation error , I don't remember ever doing a GH-040-02 before and finding a diagram was a small challenge too , are they uncommon revisions?!

 

Re-check (and resolder) A, B, F, G, H, I and Y points.
In worst case, i know it's a pain, you need to soolder wire directly to the mechacon...

 

I'll re-do them then, for the 3rd time (did them again when I found about the problem).
There is no F though, maybe it's for older modbo or something...

 

I give up. I put a tested laser, I can boot originals. No dice with backups.
I re-did A-B-G-H-I and verified direct connection to mechacon. I soldered Y directly to mechacon as per another schematic I found (only Y was different). I even replaced the modchip with another new one. I am out of ideas atm.
Console is a PAL 75004 btw.


edit:
I found this picture here



so I tried the new Y point , I was able to boot once a backup but nothing after that... the disc just spins and changes speeds without any results.

 

Might be just your discs, since it can identify the disc correctly, and even read and decrypt the PS2 logo from the disc. Use Verbatim DVD-R discs that were manufactured by either Taiyo Yuden or Mitsubishi.

I know that you wrote that your discs are good, but only Verbatim DVD-R by these manufacturers are known to be the best.
Even if you replaced the laser, the calibration for the drive might be too off for the laser to work.

 

logo decryption doesn't always happen... but the struggle is great LOL
I'll just mod another ps2 for him, this already took a long time. If it can't read ritek discs then it's not that good to begin with IMHO

edit:
I just did a quick transplant of the modchip + wires to a stock GH-051-02 , everything works perfect with the same backup discs.
I think there is a possibility some points differ on the GH-040-02 mobo, maybe diagrams are for NTSC mobos or something....