The Business Activity Exclusion

What happens if you operate a business – say an auto repair shop – as a means of making a living, and then suffer a fire loss to personal property located in that business? Assume the fire occurs as a result of working on a car in your repair shop, but that at the time of the fire you were not actually engaged in business; rather, you were working on your own car, or perhaps helping a friend to work on her car as a favor. Would the business activities exclusion in your homeowner’s insurance policy preclude you from recovering for the loss of your personal property?