This may indicate that the battery has poor capacity.
Troubleshooting Tips: Check the battery voltage under charge. If the battery measures less than normal (6-volts or 12-volts depending on the system), momentarily press the test switch and see if the battery voltage begins to increase about 1.5 minutes. If it does, the charger is fine, replace the battery. If battery voltage measures greater than nominal (6-volts or 12-volts depending on the system) and the status indicator is red, the charger board will likely need to be replaced.