Interpreting System Validation Diagnostic Front Panel Leds And Audible Codes - HP ProDesk 405 G4 Small Form Factor Maintenance And Service Manual

Control panel message
90D-System Temperature
90E-Power Supply Fan Not detected
910–Filter Warning
Interpreting system validation diagnostic front panel LEDs and
audible codes
During the system validation phase that occurs at system startup, the BIOS validates the functionality of
the following subsystems and conditions:
AC adapter
●
System board power
●
Processor failure
●
BIOS corruption
●
Memory failure
●
Graphics failure
●
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:
Major – the category of the error
●
Minor – the specific error within the category
●
NOTE: Single beep/blink codes are not used.
Number of long beeps/blinks
1
2
3
4
5
Description
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
malfunctioned.
Airflow filter is dirty.
Error category
Not used
BIOS
Hardware
Thermal
System board

Interpreting system validation diagnostic front panel LEDs and audible codes 103

Recommended action
3. Replace fan.
Make sure system has proper airflow.
1. Reseat power supply fan.
2. Reseat fan cable.
3. Replace power supply fan.
Replace the airflow filter.