First of all, there are many factors that affect the abnormal operation of the whole solar power system. Generally, the correct maintenance order is to measure the voltage of the battery is normal or not. If the voltage of the battery is not normal, low or high may lead to the solar system not working.

       Second, make sure that the solar panel works properly, whether the solar panel parameters meet the requirements of the solar charge controller, whether the installation angle is correct, whether there are rainy days, and whether the power of the solar panel meets the requirements (some time there will be a false mark phenomenon).

       Third, whether the load is normal, whether there is overload, short circuit, or the load working parameters do not match.

       Fourth, verify that the controller status LED is normal.

       If you suspect the controller  failure, you can use the same type of replacement method to confirm, once found the controller itself quality problems, please contact the manufacturer for technical guidance.