These lights should be visible after removing the service door or bottom
cover. Consult with support for platform-specific locations of the lights.
●
Example: System board is good. Lights that turn on briefly (< 1 second) and immediately turn off indicate
normal function. In this case, system (3.3V), power good (3.3V), and system reset (3.3V) are all good and
troubleshooting lights should not be lit. However, other external lights should be lit as normal
afterward.
Troubleshooting lights
External lights
Action
Note
Off
On
Do not replace system board
No power-on issue
On
Off
Replace board
Power-on issue
●
Example: System board needs replacement. When (1) system 3.3V exists, but one power rail is bad then
(2) power good is low (0V), and troubleshooting lights will turn on.
After you press the system power button, troubleshooting lights will turn on for 5 seconds and turn
off. The system external lights will not light up. Follow general troubleshooting steps (i.e., remove
recently added hardware, test with minimum configuration, etc.) prior to replacing the system board.
Resolve the issue
8. Hard reset
A hard reset or forced reset (
http://support.hp.com/us-en/document/c01684768
) erases all information in
the computer's memory and may restore functionality. Resetting the computer forces the system to clear and
reestablish the connections between the BIOS and the hardware.
IMPORTANT:
Battery removal is NOT necessary for a hard reset on G3 or G4 mobile workstations. Follow the
instructions for a computer with a non-removable battery.
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Chapter 6 Troubleshooting guide