mod # ? probably thermocouple,dometic specific part about 60.00 r&r t couple and on bench attach meter set to mil. volts heat end should read at least 30 mv if not replace. if replacement of t-couple still won't stay lit safety valve is bad.can be purchased as seperate part if local dealer with access to dometic direct is willing. first step before you take anything apart is to check lpg press with flame lit (hold button)10-12" water columne is apropriate. also clean burner and orfis may help.make sure t-couple is in flame.may have used t-couple e me if tou need it,don't sell used parts you pay freight.