When it is turned on and you have signal going into the effect, try to gently bend the pots around to see if you can do anything to get signal to come through the circuit. Give special attention to the volume pot…that’s the one pot that has direct control over the output signal. You can also try to poke and press on various components on the board to see if that makes any difference. The goal here it to figure out which component is shorting the signal or keeping it from passing through.