Lenovo ThinkCentre M50e, Hardware Maintenance Manual

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1. Turn off the computer and disconnect all external devices.
2.
Power-on the computer.
3. There are three LEDs to help you determine if the power supply and system
board are working correctly. The power button LED is located on the front of
the computer and the two diagnostic LEDs are located on the power supply at
the rear of the computer. After pressing the power button, observe the LEDs
and refer to the following table:
Power LED
Green
diagnostic LED
Yellow
diagnostic LED Action
ON ON OFF This is the normal condition of the LEDs when the power is
OK.
OFF OFF OFF
v
Make sure the power cord is attached to a working
electrical outlet.
v
Check the power cord for continuity.
v
If the problem persists, replace the power supply.
OFF (after the
power button
has been
pressed)
ON OFF Replace the system board
ON ON ON Replace the power supply
If the Diagnostic LEDs are in the normal condition and the problem persists,
replace the system board and the microprocessor, one at a time, until the
computer works correctly.
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Hardware Maintenance Manual