Yamaha Chorus CH10MII Pedal Not Working

[bass_econo]

Hello,

I'm new to the forums.

I recently bought a CH10MII chorus from a guy on ebay and now that I have it it is not working.  I get sound when it is off, when it is on the volume drops slightly but no effect.  I have turned the amp way up but I do not hear any clicking, pulsing or anything.  I have searched for but cannot find the schematic for the pedal, but I am also afraid to open the box if there is no hope.  

 I really want the pedal but if there is no hope I will try to get my money back.

- Thanks