About Your System 15
Diagnostic Lights

The four diagnostic indicator lights on the system front panel display error

codes during system startup. Table1-1 lists the causes and possible corrective

actions associated with these codes. A highlighted circle indicates the light is

on; a non-highlighted circle indicates the light is off.

Table 1-1. Diagnostic Indicator Code
Code Causes Corrective Action
The system is in a normal
off condition or a possible
pre-BIOS failure has
occurred.
The diagnostic lights are
not lit after the system
successfully boots to the
operating system.
Plug the system into a working
electrical outlet and press the
power button.
The system is in a normal
operating condition after
POST.
Information only.
BIOS checksum failure
detected; system is in
recovery mode.
See "Getting Help" on page 123.
Possible processor failure. See "Troubleshooting the
Processor" on page113.
Memory failure. See "Troubleshooting System
Memory" on page 107.
Possible expansion card
failure.
See "Troubleshooting Expansion
Cards" on page 112.
Possible video failure. See "Getting Help" on page 123.