Using a multimeter to check terminal voltage, the battery voltage reading is low or there is no voltage at the terminal. Possible causes for this problem are:
- The voltage of a cell within the battery has dropped below 2V causing the microprocessor to enable under-voltage protection.
- The battery’s state-of-charge (SOC) has dropped below 5% from an extended idle period or heavy use, enabling under-voltage protection.
- The battery has overheated causing the microprocessor to enable over-temperature protection.
To resolve situations where terminal voltage is absent or low:
- Allow the battery to cool and recheck terminal voltage.
- Connect the battery to a charger to wake the battery and recover terminal voltage. Depending on the battery’s voltage and state of balance, it may take up to 48 hours to completely charge and balance the battery.