Control panel message
903-Computer Cover Has Been Removed Since
Last System Startup
904-SATA Cabling Error
90E-Power Supply Fan Not detected
Interpreting system validation diagnostic front panel LEDs and
During the system validation phase that occurs at system startup, the BIOS validates the functionality of the
following subsystems and conditions:
System board power
System board failure
BIOS authentication failure
If an error is detected, specific patterns of long and short blinks, accompanied by long and short beeps (where
applicable) are used to identify the error. These patterns will make up a two part code:
One or more SATA devices are improperly
attached. For optimal performance, the SATA 0
and SATA 1 ports should be used for hard drives
before other ports.
The system has detected that a cooling fan is
not operating correctly.
Thermal shutdown occurred. The system BIOS
has detected your machine was previously shut
down to avoid overheating. Overheating may
occur if the cooling vents are blocked or the
operating temperature exceeds the system
specifications. The machine should return to
normal operation once the situation is resolved.
Power supply fan is not connected or may have
Airflow filter is dirty.
Only HP modules are supported. Unrecognized
modules will not be enabled.
Interpreting system validation diagnostic front panel LEDs and audible codes
Replace chassis, rear chassis, or front
Ensure SATA connectors are used in ascending
order. For one device, use SATA 0. For two
devices, use SATA 0 and SATA 1. For three
devices, use SATA 0, SATA 1, and SATA 2.
Reseat fan cable.
Make sure system has proper airflow.
Reseat power supply fan.
Reseat fan cable.
Replace power supply fan.
Replace the airflow filter.
Only use supported HP modules.