Checking Operational Charging.
To check operational charging, use a discharged battery pack or a battery pack that has less than 50% of the total power remaining when installed in the computer.
Perform operational charging. If the battery status indicator does not turn on, remove the battery pack and let it return to room temperature. Reinstall the battery pack. If the charge indicator still does not turn on, replace the battery pack.
If the charge indicator still does not turn on, replace the system board. Then reinstall the battery pack. If the reinstalled battery pack is not charged, go to 'Checking the Battery Pack'