Hi all,i have a singer 2502c sewing machine,the issue is with the foot switch,it is either on or off,there is no ramp up of the power,its like flatout or nothing,so far i have tested the bt134 triac with a dmm,it seems fine,any ideas what the issue could be,would a duff cap or diac cause this?,i have measured the caps for s/c they are not shorted,not cheched capacitance yet or esr.attached is a pic of the pcb,have no idea of the history as just brought it for spares or repair. tia