NEC D3 Quick Start Manual page 8

Controller Status LEDs
There are three status LEDs on each controller that include, from left to right, a Backup LED, a Fault LED,
and a Ready LED. The Backup LED will only blink to indicate that the battery backup is currently powering
the unit. The Ready and Fault LEDs use the following signal combinations to indicate controller status.
Ready LED Fault LED
Blinking
ON
Rapid Blinking
Asynchronous Blinking
Synchronized Blinking
ON
ON Blinking
Blinking
OFF
NEC D3/D4 Quick Start Guide
OFF Normal operating condition
OFF Startup sequence in progress
OFF Shutdown sequence in progress
Online/automatic download sequence in progress
In download mode
ON Fault condition exists
Waiting for disk enclosure power-on
ON Disk interface is disabled
OFF Powered off
Table 5. Controller Ready LED and Fault LED Status Conditions
Status
6