Component identification  21 
  
LED3 pattern  LED4 pattern  Interpretation 
Off 
Flashing (2 Hz)  The system is powered down, and the cache contains data that has not 
yet been written to the drives. Restore system power as soon as 
possible to prevent data loss. 
Data preservation time is extended any time that 3.3 V auxiliary 
power is available, as indicated by LED 2. In the absence of auxiliary 
power, battery power alone preserves the data. A fully-charged 
battery can normally preserve data for at least 2 days. 
The battery lifetime also depends on the cache module size. For more 
information, see the controller QuickSpecs on the HP website 
(http://www.hp.com). 
Off 
Double flash, then 
pause 
The cache microcontroller is waiting for the host controller to 
communicate. 
Off 
Flashing (1 Hz)  The battery pack is below the minimum charge level and is being 
charged. Features that require a battery (such as write cache, capacity 
expansion, stripe size migration, and RAID migration) are unavailable 
temporarily until charging is complete. The recharge process takes 
between 15 minutes and 2 hours, depending on the initial capacity of 
the battery. 
Off 
On  The battery pack is fully charged, and posted write data is stored in the 
cache. 
Off 
Off  The battery pack is fully charged, and no posted write data exists in 
the cache. 
Flashing (1 Hz) 
Flashing (1 Hz)  An alternating green and amber flashing pattern indicates that the 
cache microcontroller is executing from within its boot loader and 
receiving new flash code from the host controller. 
On 
—  A short circuit exists across the battery terminals or within the battery 
pack. BBWC features are disabled until the battery pack is replaced. 
The life expectancy of a battery pack is typically more than 3 years. 
Flashing (1 Hz) 
—  An open circuit exists across the battery terminals or within the battery 
pack. BBWC features are disabled until the battery pack is replaced. 
The life expectancy of a battery pack is typically more than 3 years.