1. It may be that the voltage is overcharged, overdischarged, overcurrent, short circuit and overtemperature;

2. Use a multimeter to measure whether the charge-discharge MOS tube is turned on;

3. If the lithium battery protection board is LED, it can't be charged and discharged, and the LED flashes for 0.5 seconds to give an alarm;

4. If the lithium battery protection board is equipped with an upper computer, it can be connected to the upper computer to check the protection status;

5. The lithium battery pack protection board has a weakness switch. Please check whether the weakness switch is turned on.

    Because of the activity of lithium ion, the protective plate must be used to prevent the lithium battery from overcharging and discharging.

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