Boss GE-7 EQ Help

[Erocku]

I just aquired a BOSS GE-7 EQ from a friend that is broken. When off, the sound will pass through. When the pedal is engaged, there is no sound at all, just some faint noise. I can move the sliders and the noise changes, so it looks like they are working. Does anyone have any tips, or give me an idea of where to start to try and fix the problem? Thanks.

[nooneknows]

The trannies that pilotes the fet switching have gone? The op amp section is broken? A lot of things can happen.
Try building a simple probe (there is a thread around) and, with the pedal on, from the output track back the signal until it disappears, i think it's the only way to know where's the failure