The power windows use a circuit breaker to protect the circuit and not a normal fuse. This way if the power gets shorted the breaker will reset itself and hopefully the short has cleared also. The click you hear is most likely coming from the breaker as it trips and removes power to the circuit. From what you say it sounds like there is a short on the power window circuit. If the clicking occurs even if you are not trying to move the windows then the short is before the switch console in the driver's door.