Rodents do a lot of damage to wiring in these situations. To begin, make sure the electrical power to your equipment is Locked in the OFF Position at the main disconnect. Extreme caution should always be used when working around electrical power boxes and machinery. If you are not sure the power is off, check it with a voltmeter to make sure the power is truly disconnected. Electric motors and phase convertors are especially susceptible to rodents, dust and moisture accumulations.
High winds can deposit snow and fine dust inside presumably sealed boxes.
If possible, open the motor for better access to the windings. Using compressed air, remove any dirt and dust. While the motor is open check for rodent entry and damage. If there is evidence of rodent damage, find the entry hole and plug it. Check the motor shaft to see that it turns freely.