② Installing third-party software from unknown sources or brushing in third-party rom packages from unknown sources may infect malicious programs, and it will still consume power and heat after shutdown. You can try to brush back the official ROM package.
③ Non-original batteries and old batteries are likely to be incompatible with this machine or have quality problems, thus showing power consumption and fever. You can try to replace the original battery.
(4) The fuselage is immersed in a liquid and humid environment, and the low-temperature environment quickly shifts to a high-temperature environment. Due to serious bumps and unexpected defective products, the motherboard will be corroded or mechanically damaged, resulting in short circuit or overload of individual components. If you have such a history, you can contact the after-sales seller for maintenance or consider changing the machine.
PS: If you give it to the after-sales seller, you will probably brush the official ROM package, replace the original battery, and disassemble it to check whether the motherboard is normal.