After inserting the batteries, happened only once nothing. I thought I might have the batteries been inserted upside down. Tried all directions. Nothing. My husband 'repaired' it then and told me that when inserting the batteries, the light is bridged and therefore nothing will happen, he handled the whole in which he. A piece of paper with inlaid Through a loose connection or other times it works, or sometimes not. Once there is any problem and then pushes you to be dead and nothing happens and eventually hours later we arrive at his bike and it flashes. useless!
