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General checkout

General checkout
This chapter presents the following information:
• “What to do rst” on page 20
• “Power system checkout” on page 21
Before you go to the checkout, make sure to read the following important notes:

Important notes:

• Onlycertiedtrainedpersonnelcanservicethecomputer.
• BeforereplacinganyFRU,read theentirepageonremovingand replacing
FRUs.
• WhenyoureplaceFRUs,usenewnylon-coatedscrews.
• Beextremely carefulduring suchwrite operationsa scopying,s aving,or
formatting. Drives in the computer that you are servicing sequence might
have been altered. If you select an incorrect drive, data or programs might be
overwritten.
• Replacean FRUonly withanother FRUofth ecorrectmo del. When y ou
replace an FRU, make sure that the machine model and the FRU part number are
correct by referring to the FRU parts list.
• AnFRUshouldnotbe replacedjustbecauseof asingle,unreproducible
failure.Single failures can occur for a variety of reasons that have nothing to
do with a hardware defect, such as cosmic radiation, electrostatic discharge, or
software errors. Consider replacing an FRU only when a problem recurs. If you
suspect that an FRU is defective, clear the error logs and run the test again. If the
error does not recur, do not replace the FRU.
• BecarefulnottoreplaceanondefectiveFRU.