Check the power adapter is good or bad a multimeter is enough to see whether the output end has voltage or voltage is low (the voltage of the notebook adapter is generally between 16v- 20v, see the mark of your adapter) If it is a simple short line or the output end is bad, it can be replaced by itself, if the power transformer is partially damaged, as said upstairs, it is not recommended to do it yourself. The power adapter of the notebook is sealed with glue and can only be pry open. Inside is an AC to DC transformer, a circuit board several capacitors, and a circuit board. And the adapter maintenance value is not large, and the stability is not good, it is recommended to replace directly, the owner of the electronic should understand its internal, when buying, you do not need to buy the original, high imitation can be. That kind of simple AC converter, it's really not flattering. In summary, it's the transformer, so don't fix it.