Automobile warning device and warning method

The invention belongs to the technical field of automobile parts, and particularly relates to an automobile warning device which comprises a light guide plate forming an automobile body exterior trim panel or attached to the automobile body exterior trim panel, and the light guide plate is communicated with a light source. The arrangement position of the light guide plate is easy to observe, pedestrians around the vehicle can immediately recognize the vehicle and notice the vehicle, and therefore collision accidents are avoided. The warning method applying the automobile warning device comprises the steps that the radar probe detects obstacles in front of and behind the automobile and uploads obstacle information to the automobile body controller, and when the obstacles exist in front of or behind the automobile and the distance between the obstacles and the automobile body is smaller than a set warning threshold value, the automobile body controller gives out an instruction to enable the light source to be p