Hardware replacement proceduresControllersReplace a controllerRemove failed controllerStep 2: Remove batteryRemove batteryYou remove the battery so you can install the new controller.Remove the controller canister's cover by pressing down on the button and sliding the cover off. Confirm that the green LED inside the controller (between the battery and the DIMMs) is off.If this green LED is on, the controller is still using battery power. You must wait for this LED to go off before removing any components. Internal Cache Active LED BatteryLocate the blue release latch for the battery.Unlatch the battery by pushing the release latch down and away from the controller canister. Battery release latchBatteryLift up on the battery, and slide it out of the controller canister.Go to Remove host interface card.Give documentation feedback