Mice are not afraid of light. But they are cautious about movement. But if you are doing long stay camping they do begin to get used to the moving lights after a week or so and begin ignoring it. Rodents are pretty clever creatures.I thought the hood was supposed to be open because rodents don't like being exposed. They prefer an enclosed dark space. So we SHOULD leave it open at night. With a light on the engine bay, if possible.