HP ZBook 15 G4 - Resolve the Issue; Hard Reset

troubleshooting lights should not be lit. However, other external lights should be lit as normal
afterward.
Troubleshooting lights External lights Action Note
O On Do not replace system board No power-on issue
On O 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
o. The system external lights will not light up. Follow general troubleshooting steps (i.e., remove
recently added hardware, test with minimum conguration, 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.
Performing a hard reset might x the following common conditions:
●
Windows stops responding.
●
Computer stops before Windows loads, indicated by incomplete boot-up, blinking cursor on a black
background, and errors relating to operating system not found or a missing drive.
●
Display suddenly goes blank and stays blank.
●
Software freezes.
●
Keyboard stops responding.
●
The computer does not exit Sleep or Suspend state.
●
An external device stops responding. Turn o the power to that device in addition to performing the
steps in this document.
Before performing a hard reset, you must disconnect or remove all peripheral devices. You should start and
test the computer by itself, and if the problem is not resolved, reconnect one peripheral device at a time. To
resolve the startup or operational problem, run HP Support Assistant, or manually install all updated drivers
from Microsoft and HP.
Before beginning, turn the computer over and look for a battery compartment door (service door). For 2015
platforms, the battery is considered removable but not accessible. See the battery section for how to remove/
unplug the battery.
To perform a hard reset on a computer with a sealed or non removable battery, use the following steps:
1. Turn o the computer.
2. Remove the computer from any port replicator or docking station.
General troubleshooting steps 89