hotpoint ultima tdc60 heating relay?

hello, i've got a problem with the heating element not being called for on the drying cycle of my hotpoint ultima tdc60...there is no voltage to the thermal cut off device. the heating light shows quickly then its goes out. i have tried linking out the tcd so i can only assume it is the relay, there are three on the pcb does anyone know which one it is? or if it could be anything else, maybe the rotary switch....the cycles all work normally but theres no voltage to the heating element and i have linking the thermal cut out cables...i cant find any wiring diagrams on line...many thanks john p