1. The charging lamp power switch is faulty. You can short-circuit the two pins of the switch to check whether the indicator light can light up normally. If it can light normally, it indicates that the key switch is damaged and can be replaced. If no, the fault is in the subsequent circuit.
2. The booster plate is faulty. The detection of the booster plate fault can only be measured by a multimeter. Press the power switch, the multimeter is set to DC voltage, the black watch pen is grounded, and the red watch pen starts from the correct pole of the voltage output of the charging bank to measure the voltage of the pins of the relevant components in reverse. If the voltage is measured to a component, then the faulty component is the component after it, and it can be replaced.