Service Reference Guide, dc5100
376220-001
C–7
POST Diagnostic Front Panel LEDs and Audible Codes
This section covers the front panel LED codes as well as the audible codes that may occur before
or during POST that do not necessarily have an error code or text message associated with them.
✎
If you see flashing LEDs on a PS/2 keyboard, look for flashing LEDs on the front panel of the
computer and refer to the following table to determine the front panel LED codes.
✎
Recommended actions in the following table are listed in the order in which they should be
performed.
✎
Beeps will occur only for 5 iterations and then stop. LEDs will continue to blink until corrective
action is taken.
POST Diagnostic Front Panel LEDs and Audible Codes
Activity
Beeps
Possible
Cause
Recommended Action
Green Power LED
On.
None
Computer on.
None
Green Power LED
flashes every two
seconds.
None
Computer in
Suspend to RAM
mode (select
models only) or
normal Suspend
mode.
None required. Press any key or move the
mouse to wake the computer.
Red Power LED
flashes two times,
once every
second, followed
by a two second
pause. Beeps stop
after the fifth
iteration but the
LED continues to
flash until the issue
has been resolved.
2
Processor
thermal
protection
activated:
A fan may be
blocked or not
turning.
OR
The heatsink/fan
assembly is not
properly
attached to the
processor.
Ensure that the computer air vents are not
blocked and the processor cooling fan is
running.
Open hood, press power button, and see
if the processor fan spins. If the processor
fan is not spinning, make sure the fan's
cable is plugged onto the system board
header. Ensure the fan is fully/properly
seated or installed.
If fan is plugged in and seated properly,
but is not spinning, then replace processor
fan.
Reseat processor heatsink and verify that
the fan assembly is properly attached.
Contact an authorized reseller or service
provider.