IBM TotalStorage 300 Service Manual page 107

4. Use the storage-management software to locate the RAID controller containing
the failed battery (the RAID controller Fault LED might be on).
5. Label each cable that connects to the RAID controller that contains the battery
that has failed. This ensures that all cables will be properly reconnected to the
RAID controller after you replace the battery.
6. Use the storage-management software to take the RAID controller offline that
contains the battery that has failed.
7. From the RAID controller that contains the battery that has failed, remove the
Fibre Channel cables and then the GBICs.
8. Remove the RAID controller as described in "Replacing a RAID controller" on
page 93.
9. Using a Phillips head screwdriver, remove the eight screws from the battery
access panel on the bottom of the RAID controller CRU, as shown in the
following illustration.
Battery-access panel
10. Lift the old battery out of the RAID controller CRU.
Note: If you cannot lift out the battery, turn over the RAID controller holding it
upside-down close above a flat surface and let it fall out. Do not let the
weight of the battery pull on the battery harness.
11. Disconnect the battery harness on the old battery from the two-pin connector
on the controller board, and remove the battery, as shown in the following
illustration.
Battery
Battery harness
Chapter 5. Installing and replacing IBM NAS 300 components
Two-pin connector
97