It used to be a trend - Young drivers had the car's engine bonnet covered with fake carbon fiber sticker. For what? I suppose because the real WRC cars have carbon fiber parts to lighten them... Anyway, here is a very simple test that you can make with the multimeter and test if the carbon-fiber is real carbon fiber. I suppose that if it beeps it means that MOST LIKELY (not 100%) it is real carbon fiber. But if it does not, it definitely means that its is NOT carbon fiber.