I've just repaired one with a similar issue. Sometimes you would get an odd character light up on the display, apart from that totally dead. Turned out to be the capacitor feeding the 12v regulator 35v 1000uf. I have just uploaded a video on YouTube diagnosing the problem, and repairing it. -BuyItFixIt

I have just just repaired one of these fans that had 3 faults. The F2 error (motor not turning) which needed a replacement motor as it had burned out, and also replacing the oscillation motor, and repairing the PCB as the fan was oscillating all the time when the power was applied. "BuyItFixIt" on youtube.