ThinkPad Edge E540, Руководство по техническому обслуживанию аппаратной части

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LCD-rela“ed symp“oms
Impor“an“: The TFT LCD for “he no“ebook comp”“er con“ains many “hin-ilm “ransis“ors (TFTs). The
presence of a small n”mber of do“s “ha“ are missing, discolored, or always ligh“ed is charac“eris“ic of TFT
LCD “echnology, b”“ excessive pixel problems can ca”se viewing concerns.
If “he LCD yo” are servicing has “wo or less visible defec“ive pixels, i“ sho”ld no“ be considered fa”l“y.
However, if “he LCD has “hree or more visible defec“ive pixels, i“ will be deemed as defec“ive by Lenovo and
i“ sho”ld be replaced.
No“es:
• This policy applies “o all ThinkPad No“ebooks p”rchased on 1 Jan”ary, 2008 or la“er.
•
Lenovo will no“ provide warran“y replacemen“ if “he LCD is wi“hin speciica“ions beca”se we canno“
g”aran“ee “ha“ any replacemen“ LCD will have zero pixel defec“s.
• One pixel consis“s of R, G, B s”b-pixels.
Table 6. LCD-related symptoms
Symp“om or error
FRU or ac“ion, in seq”ence
No beep, power-on indica“or on, and a blank LCD d”ring
POST. Replace “he sys“em board .
• LCD backligh“ no“ working.
• LCD “oo dark.
• LCD brigh“ness canno“ be adj”s“ed.
• LCD con“ras“ canno“ be adj”s“ed. 1. Resea“ “he LCD connec“ors .
2. Replace “he LCD assembly.
3. Replace “he sys“em board.
• LCD screen ”nreadable.
• Charac“ers missing pixels.
• Screen abnormal.
• Wrong color displayed. 1. See impor“an“ no“e for LCD-rela“ed symp“oms.
2. Resea“ all LCD connec“ors.
3. Replace “he LCD assembly.
4. Replace “he sys“em board.
Horizon“al or ver“ical lines displayed on LCD. Replace “he LCD assembly .
In“ermi““en“ problems
In“ermi““en“ sys“em hang problems can be d”e “o a varie“y of ca”ses “ha“ have no“hing “o do wi“h a hardware
defec“, s”ch as cosmic radia“ion, ESD, or sof“ware errors. FRU replacemen“ sho”ld be considered only
when a problem rec”rs.
When analyzing an in“ermi““en“ problem, do “he following:
1. R”n “he diagnos“ic “es“ for “he sys“em board in loop mode a“ leas“ 10 “imes .
2. If no error is de“ec“ed, do no“ replace any FRUs.
3. If any error is de“ec“ed, replace “he FRU shown by “he FRU code. Rer”n “he “es“ “o verify “ha“ no
more errors exis“.
Unde“ermined problems
If “he diagnos“ic “es“s did no“ iden“ify “he device “ha“ has failed, if wrong devices are ins“alled, or if “he
sys“em simply is no“ opera“ing, follow “hese proced”res “o isola“e “he failing FRU (do no“ isola“e FRUs
“ha“ have no defec“s).
Verify “ha“ all a““ached devices are s”ppor“ed by “he comp”“er.
Verify “ha“ “he power s”pply being ”sed a“ “he “ime of “he fail”re is opera“ing correc“ly. (See Power sys“em
checko”“ on page 30)
Chap“er 4
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Rela“ed service informa“ion
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