Version 7 PS2 Laser problem

[Jamey]

Hello,

Thank you for reading this. Here is what Im dealing with. I have a ps2 from a friend that is a version 7 that just stopped reading DVD disks only. Reads CD's just fine. So they can play ps1 games and a few ps2 games that are on CD of course. No modchip in this ps2 and never was to clear that up.

I tried cleaning both the top and bottem lens' of the laser with no luck. I thought I would then replace the 400c laser with my son's 400c that was in his ver7 ps2. The weird thing is that it still will not read DVD's at all. Does anyone have any idea on what this could be? Is there something else on the mainboad that could be causing this ps2 NOT to read DVD's? Thanks,

Jamey