Lenovo E420 Laptop User Manual


 
customers to install options or replace CRUs. You must closely follow all instructions when installing or
replacing parts. The Off state of a power indicator does not necessarily mean that voltage levels inside a
product are zero. Before you remove the covers from a product equipped with a power cord, always make
sure that the power is turned off and that the product is unplugged from any power source. For more
information on CRUs, refer to the Replacing devices for this product. If you have any questions or concerns,
contact the Customer Support Center.
Although there are no moving parts in your computer after the power cord has been disconnected, the
following warnings are required for your safety.
DANGER
Hazardous moving parts. Keep ngers and other body parts away.
CAUTION:
Before replacing any CRUs, turn off the computer and wait three to ve minutes to let the computer
cool before opening the cover.
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