1. "220V AC Cooling Fan" observe the law: the power is with the eye sockets, switches, speed parts, mechanical transmission components for visible signs of loosening, fracture obvious features, such as burning, and if so, where may be faulty. Then proceed to exclude.
2. "220V AC Cooling Fan" replace the law; to start capacitor, the governor, to be replaced with a good motor spare parts, if they can work properly, the original component damage.
3. "220V AC Cooling Fan" measuring the resistance method:
(1) start capacitor: Use a multimeter to check the resistance profile of charge, without charging phenomenon (the first hours after the larger resistance), the capacitor leakage or breakdown.
(2) Motor: measuring the motor winding resistance, compared with the normal value, the difference is large, the malfunction.