Dell Precision T1600, Service Manual, Page: 66 / 89

Light Pattern
Problem Description Troubleshooting
Steps
Diagnostic LEDs Power Button LED
• Ensure that any
power strips
being used are
plugged into an
electrical outlet
and are turned
on.
• Ensure that the
electrical outlet
is working by
testing it with
another device,
such as a lamp.
• Ensure that the
main power
cable and front
panel cable are
securely
connected to
the system
board.
A possible system
board failure has
occurred. Unplug the
computer. Allow
one minute for the
power to drain. Plug
the computer into a
working electrical
outlet and press the
power button.
A possible system
board, power
supply, or peripheral
failure has
occurred.
• Power off
computer,
leaving the
computer
plugged in.
Press and hold
the power
supply test
button at the
rear of the
power supply
unit. If the LED
next to the
switch
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