Dell OptiPlex SX270 - Manual (Page 82)

Diagnostic Lights
To help you troubleshoot a problem, your computer has four lights labeled "A," "B," "C," and "D" on the back panel. The lights can be yellow or green. When
the computer starts normally, the patterns or codes on the lights change as the boot process completes. If the POST portion of system boot completes
successfully, all four lights display solid green. If the computer malfunctions during the POST process, the pattern displayed on the LEDs may help identify
where in the process the computer halted.
CAUTION: Before you begin any of the procedures in this section, follow the steps in " CAUTION: Safety Instructions ."
Light Pattern Problem Description Suggested Resolution
off
off
off
off The computer is in a normal
off condition or a possible
pre-BIOS failure has
occurred. Verify that the computer is plugged into a working electrical outlet and that you have pressed the
power button.
green
yellow
yellow
yellow A possible BIOS failure has
occurred; the computer is in
the recovery mode. Run the BIOS Recovery utility, wait for recovery completion, and then restart the computer.
yellow
green
yellow
yellow A possible microprocessor
failure has occurred. Reinstall the microprocessor and restart the computer.
green
green
yellow
yellow Memory modules are
detected, but a memory
failure has occurred. l If you have one memory module installed , reinstall it and restart the computer.
l If you have two or more memory modules installed, remove the modules, reinstall one
module, and then restart the computer. If the computer starts normally, reinstall an
additional module. Continue until you have identified a faulty module or reinstalled all
modules without error.
l If available, install properly working memory of the same type into your computer.
l If the problem persists, contact Dell .
yellow
yellow
green
yellow A possible expansion card
failure has occurred. 1. Determine if a conflict exists by removing a card (not the video card) and then restarting
the computer.
2. If the problem persists, reinstall the card that you removed, remove a different card, and
then restart the computer.
3. Repeat this process for each card. If the computer starts normally, troubleshoot the last
card removed from the computer for resource conflicts (see " Resolving Software and
Hardware Incompatibilities ").
4. Move each card one at a time to a different PCI slot and restart the computer after each
move.
5. If the problem persists, contact Dell .
green
yellow
green
yellow A possible video card failure
has occurred. l If the computer has a video card, remove the card, reinstall it, and then restart the
computer.
l If the problem still exists, install a video card that you know works and restart the
computer.
l If the problem persists or the computer has integrated video, contact Dell .
yellow
green
green
yellow A possible floppy or hard
drive failure has occurred. Reseat all power and data cables and restart the computer.
green
green
green
yellow A possible USB failure has
occurred. Reinstall all USB devices, check cable connections, and then restart the computer.
yellow
yellow No memory modules are
detected. l Reinstall all memory modules and restart the computer.
l To eliminate the possibility of a faulty memory connector, remove all memory modules,