1. If the solar panel breaks down and does not generate electricity, the controller cannot sense current, it will be considered as dark, so the light will be on during the day.

2. The positive and negative poles of the solar panel are connected reversely, and the power generated cannot be charged into the controller. The controller will also think it is dark, so the light will not be on.

3. The junction box of the solar panel is not well welded, which may lead to faulty welding, resulting in no power transmission, and the light will be on during the day.

4. Controller problem. The charging module in the controller is broken down, causing the controller to be unable to charge and the light will be on during the day.

5. Weather reasons. There are few reasons for this. In rainy weather, the solar radiation absorbed by the solar panel is insufficient and the power output is weak. The controller will think it is dark and turn on the light automatically.

6. The time in the controller is disorderly. The light is on for more than 12 hours every day, and the light will be on during the day.

The above are the 6 reasons why solar street lamps are on during the day. If your solar street lamps are on during the day, please eliminate them one by one according to the above reasons.