Sun Enterprise 220R Server Service Manual

7.12.1.2 Keyboard LEDs

Four LEDs on the Sun Type-5 keyboard are used to indicate the progress and results of POST diagnostics. These LEDs are on the Caps Lock, Compose, Scroll Lock, and Num Lock keys as shown below.


Note -

A keyboard is not shipped with the system. To read keyboard LEDs you must obtain a keyboard of the appropriate type (see the following graphic) and connect it to the keyboard/mouse port on the system's back panel.


Graphic

To indicate the beginning of POST diagnostics, the four LEDs briefly light all at once. The monitor screen remains blank, and the Caps Lock LED flashes for the duration of the testing.

If the system passes all POST diagnostic tests, all four LEDs light again and then go off. Once the system banner appears on the monitor screen, the keyboard LEDs assume their normal functions and should no longer be interpreted as diagnostic error indicators.

If the system fails any test, one or more LEDs will light to form an error code that indicates the nature of the problem.


Note -

The LED error code may be lit continuously, or for just a few seconds, so it is important to observe the LEDs closely while POST is running.


The following table provides error code definitions.

Caps Lock 

Compose 

Scroll Lock 

Num Lock 

Failing FRU 

On 

Off 

Off 

Off 

Main logic board 

Off 

On 

Off 

Off 

CPU module 0 

Off 

On 

On 

Off 

CPU module 1 

On 

Off 

Off 

On 

No memory detected 

On 

On 

On 

On 

Memory bank 0 

On 

On 

Off 

On 

Memory bank 1 

On 

On 

On 

Off 

Memory bank 2 

On 

On 

On 

On 

Memory bank 3 

Off 

Off 

Off 

On 

NVRAM 


Note -

The Caps Lock LED flashes on and off to indicate that POST diagnostics are running; all other LEDs are off. When the LED lights steadily, it indicates an error.