I have seen this many times, it is usually the even heat control board or a bad motor relay. the motor relay is located behind the console. there are 4 wires leading to it; check for voltage across the two larger wires with door shut and timer on and after pushing the PTS button, if 120 vac is present, the relay is not closing, check for voltage present across other two wires, if no voltage present the ETC board is faulty; if voltage is present the relay is faulty; good luck