They could be measured, you also need to do an insulation test at double the motors rated voltage too, you need to know what the readings are for a good motor, you can have windings short circuited or open circuited from overheating, but with 20 years experience as an electrician, once I open a motor up and smell it's burnt, even if it still works it's a good chance it won't work for very long. Your only chance is that there's something electronic inside burnt out if it has an inbuilt controller.
