Well, you're probably right - I don't think the mod installer will fix it now, but it's a very simple fix really. If you read the tutorials about how to take your model of PS2 apart, you then just need to make sure there isn't any solder globs stuck in between pins on the board. A magnifying glass and some patience are all that's needed. You can take a safety pin or something pointy and sharp like that, yet sturdy, and try to force the glob out of the crack - unless it appears wedged in there good, in which case you'll need some desoldering braid and a cheap soldering iron to remove it. The hardest part will be identifying the pins that are shorted.
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