On my Jenn Air sve47600b, I have replaced the control board twice in ten years. The LED is out again. All the buttons beep except the cancel/off and the only way I can turn off the broiler is at the breaker switch. Is it safe to assume it is the control board again? What is the "normal" life expectancy of the control board? I have desconnected and reconnected all power connections and ribbon. All connections look good…I appreciate your help…