HP t820 Maintenance & Service Manual page 83

Table C-3 Diagnostic Front Panel LEDs and Audible Codes (continued)
Activity
Red Power LED flashes four
times, once every second,
followed by a two second
pause. Beeps stop after fifth
iteration but LEDs continue until
problem is solved.
Red Power LED flashes five
times, once every second,
followed by a two second
pause. Beeps stop after fifth
iteration but LEDs continue until
problem is solved.
Red Power LED flashes six
times, once every second,
followed by a two second
pause. Beeps stop after fifth
iteration but LEDs continue until
problem is solved.
Beeps Possible Cause
4 Power failure (power
supply is overloaded).
OR
The incorrect external
power supply adapter is
being used on the unit.
5 Pre-video memory error.
6 Pre-video graphics error.
Interpreting POST Diagnostic Front Panel LEDs and Audible Codes
Recommended Action
1. Check if a device is causing the problem by
removing ALL attached devices. Power on
the system. If the system enters the POST,
then power off and replace one device at a
time and repeat this procedure until failure
occurs. Replace the device that is causing
the failure. Continue adding devices one at
a time to ensure all devices are functioning
properly.
2. Replace the power supply.
3.
Replace the system board.
CAUTION: To avoid damage to the memory
modules or the system board, you must unplug the
computer power cord before attempting to reseat,
install, or remove a memory module.
1. Reseat memory modules.
2.
Replace memory modules one at a time to
isolate the faulty module.
3.
Replace third-party memory with HP
memory.
4. Replace the system board.
For systems with a graphics card:
1.
Reseat the graphics card.
2. Replace the graphics card.
3. Replace the system board.
For systems with integrated graphics, replace the
system board.
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