1 x English User ManualOur products come with instructions, according to power definition is known to take which line, but the original car line order is not the same, need to use a multimeter to detect positive and negative pole, and then connect product power cord, if directly inserted or not in accordance with the normal method wiring, will burn the product.
Why no sound sometimes ,the problem is ‘horn cathode line Touching Iron’, ‘Touching Iron’ means that car horn cathode line touching car door,ground,and so on such as iron place.