140 Solving Problems
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Basic Checks:
•Check the diagnostic lights to see if the specific problem is identified.
•Test the electrical outlet: ensure that the electrical outlet is working by
testing it with a different device such as a lamp.
•While diagnosing the problem, connect the computer power cable
directly to a known working electrical outlet to ensure that the
computer turns on. Do not connect it to a power protection device,
UPS, power strip, or extension cord.
•Ensure that all power cables are firmly connected, verifying that each
power cable is adequately connected at the computer device and to
the electrical outlet.
•Check for interference: electrical appliances on the same circuit or
operating in close proximity to the computer can cause interference.
•Test the power cable: swap the power cables between the computer
and the monitor to see whether the problem symptoms change.
If the problem still exists after you complete the basic checks, fill out the
Diagnostics Checklist as you perform the following steps:
1Turn off the computer and devices, disconnect them from their
electrical outlets, and wait 10 to 20 seconds.
2Reconnect the computer and devices to their electrical outlets.
3Tur n o n th e co m pu t er.
Does the power light on the front of the computer light up?
Yes. The problem is resolved.
No. Go to step 4.
4Turn off the computer, swap the power cable with a known working
cable such as the monitor cable, and then turn on the computer.
Is the computer working properly?
Blinking yellow There is a system board or power supply failure.
Power Light Codes
(continued)
Power Light Cause