Lenovo IdeaCentre C540 Owner's manual

LenovoC540
HardwareMaintenanceManual
ideaideaideaCentreidea
MachineTypes:10110/6267[C540]

LenovoC540
HardwareMaintenanceManual
MachineTypes:10110/6267[C540]

FirstEdition(November2012)2nd
©CopyrightLenovo2012.
LIMITEDANDRESTRICTEDRIGHTSNOTICE:IfdataorsoftwarearedeliveredpursuantaGeneralServices
Administration“GSA”contract,use,reproduction,ordisclosureissubjecttorestrictionssetforthinContractNo.
GS-35F-05925

Contents
Chapter1.Aboutthismanual......1
ImportantSafetyInformation..........1
Chapter2.Safetyinformation......3
Generalsafety................3
Electricalsafety...............3
Safetyinspectionguide............5
Handlingelectrostaticdischarge-sensitive
devices..................5
Groundingrequirements............6
Safetynotices................6
Chapter3.Generalinformation.....9
Specications................9
Chapter4.GeneralCheckout.....11
Chapter5.UsingtheSetupUtility...13
StartingtheLenovoBIOSSetupUtilityprogram.13
Viewingandchangingsettings........13
Usingpasswords..............13
Enablingordisablingadevice........15
Selectingastartupdevice..........16
ExitingtheLenovoBIOSSetupUtilityprogram..17
Chapter6.Symptom-to-FRUIndex..19
Harddiskdrivebooterror..........19
PowerSupplyProblems...........19
POSTerrorcodes.............20
Undeterminedproblems...........20
Chapter7.Locatingconnectors,
controlsandcomponents......21
Chapter8.Replacinghardware....27
Generalinformation.............27
Replacingthekeyboardandmouse......28
Replacingtheadapter............28
Removingthestandbase..........30
Removingthefootcover...........30
Replacingamemorymodule.........31
Replacingtheharddiskdrive.........33
Replacingtheopticaldrive..........34
Removingthestandholder..........36
Removingthemiddlecover.........37
Replacingtheconverterboard........38
RemovingtheEMIcover...........39
ReplacingtherearI/Omodule........40
ReplacingtheTVtunercard.........41
ReplacingtheWLANcard..........42
Replacingthespeakersystem........43
Replacingthesystemfan..........44
Replacingtheheat-sink...........45
Replacingthecamera............46
ReplacingtheCPU.............47
Replacingthefrontcontrolboard.......50
Replacingthepowerswitchboard.......51
Replacingthemotherboard..........52
ReplacingtheLEDpanel...........53
Chapter9.FRUlists..........57
Chapter10.Generalinformation...63
AdditionalServiceInformation........63
©CopyrightLenovo2012iii

ivLenovoC540HardwareMaintenanceManual

Chapter1.Aboutthismanual
ThismanualcontainsserviceandreferenceinformationforLenovoC540All-In-Onecomputerslistedonthe
cover.ItisintendedonlyfortrainedservicerswhoarefamiliarwithLenovocomputerproducts.
BeforeservicingaLenovoproduct,besuretoreadtheSafetyInformation.
ThedescriptionoftheTV-tunercardinthismanualappliesonlytocomputerswithaTV-tunercardinstalled.
ItdoesnotapplytocomputerswithoutaTV-tunercard.
ImportantSafetyInformation
BesuretoreadallCAUTIONandDANGERsectionsinthismanualbeforefollowinganyoftheinstructions.
VeuillezliretouteslesconsignesdetypeDANGERetATTENTIONduprésentdocumentavantd’exécuter
lesinstructions.
LesenSieunbedingtalleHinweisevomTyp“ACHTUNG”oder“VORSICHT”indieserDokumentation,bevor
SieirgendwelcheVorgängedurchführen
LeggereleistruzioniintrodottedaATTENZIONEePERICOLOpresentinelmanualeprimadieseguireuna
qualsiasidelleistruzioni
Certique-sedelertodasasinstruçõesdecuidadoeperigonestemanualantesdeexecutarqualquer
umadasinstruções
Esimportantequeleatodaslasdeclaracionesdeprecauciónydepeligrodeestemanualantesdeseguir
lasinstrucciones.
©CopyrightLenovo20121

2LenovoC540HardwareMaintenanceManual

Chapter2.Safetyinformation
Thischaptercontainsthesafetyinformationthatyouneedtobefamiliarwithbeforeservicingacomputer.
Generalsafety
Followtheserulestoensuregeneralsafety:
•Keeptheareasaroundthecomputerclearandcleanduringandaftermaintenance.
•Whenliftinganyheavyobject:
1.Ensureyoucanstandsafelywithoutslipping.
2.Distributetheweightoftheobjectequallyacrossbothfeet.
3.Liftslowly.Nevermovesuddenlyortwistwhenyouattempttolift.
4.Liftbystandingorbypushingupwithyourlegmuscles;thisactionremovesthestrainfromthe
musclesinyourback.
Donotattempttoliftanyobjectsthatweighmorethan16kg(35lb)orobjectsthatyouthinkare
tooheavyforyou.
•Donotperformanyactionthatwouldcreateahazardforthecustomer,orwouldmakethecomputer
unsafe.
•Beforeyoustartthecomputer,ensurethatotherservicerepresentativesandcustomerpersonnelarenot
inapositionthatwouldcreateahazardforthem.
•Placeremovedcoversandotherpartsinasafeplace,awayfromallpersonnel,whileyouareservicingthe
computer.
•Keepyourtoolcaseawayfromareasthatpeoplemaywalkthroughtoensureno-onetripsoverit.
•Donotwearlooseclothingthatcanbetrappedinthemovingpartsofamachine.Ensurethatyoursleeves
arefastenedorrolledupaboveyourelbows.Ifyourhairislong,tieorfastenitback.
•Inserttheendsofyournecktieorscarfinsideclothingorfastenitwithanon-conductiveclip,
approximately8centimeters(3inches)fromtheend.
•Donotwearjewelry,chains,metal-frameeyeglasses,ormetalfastenersforyourclothing.
Remember:Metalobjectsaregoodelectricalconductors.
•Wearsafetyglasseswhenyouare:hammering,drillingsoldering,cuttingwire,attachingsprings,using
solvents,orworkinginanyotherconditionsthatmightbehazardoustoyoureyes.
•Afterservice,reinstallallsafetyshields,guards,labels,andgroundwires.Replaceanysafetydevice
thatiswornordefective.
•Reattachallcoverscorrectlybeforereturningthecomputertothecustomer.
Electricalsafety
CAUTION:
Electricalcurrentfrompower,telephone,andcommunicationcablescanbehazardous.Toavoid
personalinjuryorequipmentdamage,disconnectanyattachedpowercords,telecommunication
cables,networkcables,andmodemcablesbeforeyouopenthecomputercovers,unlessinstructed
otherwiseintheinstallationandcongurationprocedures.
©CopyrightLenovo20123

Observethefollowingruleswhenworkingonelectricalequipment.
Important:Useonlyapprovedtoolsandtestequipment.Somehandtoolshavehandlescoveredwithasoft
materialthatdoesnotinsulateyouwhenworkingwithliveelectricalcurrents.Manycustomershaverubber
oormatsneartheirequipmentthatcontainsmallconductiveberstodecreaseelectrostaticdischarge.
•Findtheroomemergencypower-off(EPO)switch,disconnectingswitch,orelectricaloutlet.Ifanelectrical
accidentoccurs,youcanthenoperatetheswitchorunplugthepowercordquickly.
•Donotworkaloneunderhazardousconditionsornearequipmentthathashazardousvoltages.
•Disconnectallpowerbefore:
–Performingamechanicalinspection
–Workingnearpowersupplies
–RemovingorinstallingFieldReplaceableUnits(FRUs)
•Beforeyoustarttoworkonthecomputer,unplugthepowercord.Ifyoucannotunplugit,askthe
customertopower-offtheelectricaloutletthatsuppliespowertothemachineandtolocktheelectrical
outletintheoffposition.
•Ifyouneedtoworkonacomputerthathasexposedelectricalcircuits,observethefollowingprecautions:
–Ensurethatanotherperson,familiarwiththepower-offcontrols,isnearyou.
Remember:Anotherpersonmustbetheretoswitchoffthepower,ifnecessary.
–Useonlyonehandwhenworkingwithpowered-onelectricalequipment;keeptheotherhandinyour
pocketorbehindyourback.
Remember:Theremustbeacompletecircuittocauseelectricalshock.Byobservingtheaboverule,
youmaypreventacurrentfrompassingthroughyourbody.
–Whenusingatester,setthecontrolscorrectlyandusetheapprovedprobeleadsandaccessoriesfor
thattester.
–Standonsuitablerubbermats(obtainedlocally,ifnecessary)toinsulateyoufromgroundssuchas
metaloorstripsandmachineframes.
Observethespecialsafetyprecautionswhenyouworkwithveryhighvoltages;theseinstructionsarein
thesafetysectionsofthemaintenanceinformation.Useextremecarewhenmeasuringhighvoltages.
•Regularlyinspectandmaintainyourelectricalhandtoolstoensuretheyaresafetouse.
•Donotusewornorbrokentoolsandtesters.
•Neverassumethatpowerhasbeendisconnectedfromacircuit.First,checkthatithasbeenpoweredoff.
•Alwayslookcarefullyforpossiblehazardsinyourworkarea.Examplesofthesehazardsarewetoors,
non-groundedpowerextensioncables,conditionsthatmaycauseorallowpowersurges,andmissing
safetygrounds.
•Donottouchliveelectricalcircuitswiththereectivesurfaceofaplasticdentalmirror.Thissurfaceis
conductive,andtouchingalivecircuitcancausepersonalinjuryanddamagetothecomputer.
•Donotservicethefollowingpartswiththepoweronwhentheyareremovedfromtheirnormaloperating
positionsinacomputer:
–Powersupplyunits
–Pumps
–Blowersandfans
–Motorgenerators
andsimilarunits.(Thispracticeensurescorrectgroundingoftheunits.)
•Ifanelectricalaccidentoccurs:
–Usecaution;donotbecomeavictimyourself.
4LenovoC540HardwareMaintenanceManual

–Switchoffpower.
–Sendanotherpersontogetmedicalaid.
Safetyinspectionguide
Theintentofthisinspectionguideistoassistyouinidentifyingpotentialhazardsposedbytheseproducts.
Eachcomputer,asitwasdesignedandbuilt,hadrequiredsafetyitemsinstalledtoprotectusersand
servicepersonnelfrominjury.Thisguideaddressesonlythoseitems.However,goodjudgmentshouldbe
usedtoidentifypotentialsafetyhazardsduetoattachmentoffeaturesoroptionsnotcoveredbythis
inspectionguide.
Ifanyhazardsarepresent,youmustdeterminehowserioustheapparenthazardcouldbeandwhetheryou
cancontinuewithoutrstresolvingtheproblem.
Considerthefollowingitemsandthesafetyhazardstheypresent:
•Electricalhazards,especiallyprimarypower(primaryvoltageontheframecancauseseriousorfatal
electricalshock).
•Explosivehazards,suchasadamagedCRTfaceorbulgingcapacitor
•Mechanicalhazards,suchaslooseormissinghardware
Theguideconsistsofaseriesofstepspresentedasachecklist.Beginthecheckswiththepoweroff,and
thepowercorddisconnected.
Checklist:
1.Checkexteriorcoversfordamage(loose,broken,orsharpedges).
2.Power-offthecomputer.Disconnectthepowercord.
3.Checkthepowercordfor:
a.Athird-wiregroundconnectoringoodcondition.Useametertomeasurethird-wireground
continuityfor0.1ohmorlessbetweentheexternalgroundpinandframeground.
b.Thepowercordshouldbetheappropriatetypeasspeciedinthepartslistings.
c.Insulationmustnotbefrayedorworn.
4.Removethecover.
5.Checkforanyobviousalterations.Usegoodjudgmentastothesafetyofanyalterations.
6.Checkinsidetheunitforanyobvioushazards,suchasmetallings,contamination,waterorother
liquids,orsignsofreorsmokedamage.
7.Checkforworn,frayed,orpinchedcables.
8.Checkthatthepower-supplycoverfasteners(screwsorrivets)havenotbeenremovedortamperedwith.
Handlingelectrostaticdischarge-sensitivedevices
Anycomputerpartcontainingtransistorsorintegratedcircuits(ICs)shouldbeconsideredsensitiveto
electrostaticdischarge(ESD).ESDdamagecanoccurwhenthereisadifferenceinchargebetweenobjects.
ProtectagainstESDdamagebyequalizingthechargesothatthecomputer,thepart,theworkmat,andthe
personhandlingthepartareallatthesamecharge.
Notes:
1.Useproduct-specicESDprocedureswhentheyexceedtherequirementsnotedhere.
2.MakesurethattheESDprotectivedevicesyouusehavebeencertied(ISO9000)asfullyeffective.
WhenhandlingESD-sensitiveparts:
Chapter2.Safetyinformation5

•Keepthepartsinprotectivepackagesuntiltheyareinsertedintotheproduct.
•Avoidcontactwithotherpeoplewhilehandlingthepart.
•Wearagroundedwriststrapagainstyourskintoeliminatestaticonyourbody.
•Preventthepartfromtouchingyourclothing.Mostclothingisinsulativeandretainsachargeevenwhen
youarewearingawriststrap.
•Usetheblacksideofagroundedworkmattoprovideastatic-freeworksurface.Thematisespecially
usefulwhenhandlingESD-sensitivedevices.
•Selectagroundingsystem,suchasthoselistedbelow,toprovideprotectionthatmeetsthespecic
servicerequirement.
Note:TheuseofagroundingsystemisdesirablebutnotrequiredtoprotectagainstESDdamage.
–AttachtheESDgroundcliptoanyframeground,groundbraid,orgreen-wireground.
–UseanESDcommongroundorreferencepointwhenworkingonadouble-insulatedor
battery-operatedsystem.Youcanusecoaxorconnector-outsideshellsonthesesystems.
–Usetheroundground-prongoftheACplugonAC-operatedcomputers.
Groundingrequirements
Electricalgroundingofthecomputerisrequiredforoperatorsafetyandcorrectsystemfunction.Proper
groundingoftheelectricaloutletcanbeveriedbyacertiedelectrician.
Safetynotices
TheCAUTIONandDANGERsafetynoticesinthissectionareprovidedinthelanguageofEnglish.
DANGER
Electricalcurrentfrompower,telephoneandcommunicationcablesishazardous.
Toavoidashockhazard:
•Donotconnectordisconnectanycablesorperforminstallation,maintenance,orreconguration
ofthisproductduringanelectricalstorm.
•Connectallpowercordstoaproperlywiredandgroundedelectricaloutlet.
•Connectanyequipmentthatwillbeattachedtothisproducttoaproperlywiredoutlet.
•Whenpossible,useonehandonlytoconnectordisconnectsignalcables.
•Neverturnonanyequipmentwhenthereisevidenceofre,water,orstructuraldamage.
•Disconnecttheattachedpowercords,telecommunicationscables,networkcables,andmodem
cablesbeforeyouopenthedevicecovers,unlessinstructedotherwiseintheinstallationand
congurationprocedures.
•Connectanddisconnectcablesasdescribedinthefollowingtablewheninstalling,moving,or
openingcoversonthisproductorattacheddevices.
6LenovoC540HardwareMaintenanceManual

ToConnectToDisconnect
1.TurneverythingOFF .
2.First,attachallcablestodevices.
3.Attachsignalcablestoconnectors.
4.Attachpowercordstooutlet.
5.TurndeviceON.
1.TurneverythingOFF .
2.First,removepowercordsfromoutlets.
3.Removesignalcablesfromconnectors.
4.Removeallcablesfromdevices.
CAUTION:
Whenreplacingthelithiumbattery,useonlyPartNumber45C1566oranequivalenttypebattery
recommendedbythemanufacturer.Ifyoursystemhasamodulecontainingalithiumbattery,replace
itonlywiththesamemoduletypemadebythesamemanufacturer.Thebatterycontainslithiumand
canexplodeifnotproperlyused,handled,ordisposedof.
Donot:
•Throwintoorimmerseinwater
•Heattomorethan100°C(212°F)
•Repairordisassemble
Disposeofthebatteryasrequiredbylocalordinancesorregulations.
CAUTION:
Whenlaserproducts(suchasCD-ROMs,DVD-ROMdrives,beropticdevices,ortransmitters)are
installed,notethefollowing:
•Donotremovethecovers.Removingthecoversofthelaserproductcouldresultinexposureto
hazardouslaserradiation.Therearenoserviceablepartsinsidethedevice.
•Useofcontrolsoradjustmentsorperformanceofproceduresotherthanthosespeciedherein
mightresultinhazardousradiationexposure.
DANGER
SomelaserproductscontainanembeddedClass3AorClass3Blaserdiode.Notethefollowing:
Thesediodesemitradiationwhenopen.Donotstareintothebeam,donotviewdirectlywith
opticalinstruments,andavoiddirectexposuretothebeam.
Chapter2.Safetyinformation7

≥18kg(37lbs)≥32kg(70.5lbs)≥55kg(121.2lbs)
CAUTION:
Usesafepracticeswhenlifting.
CAUTION:
Thepowercontrolbuttononthedeviceandthepowerswitchonthepowersupplydonotturnoff
theelectricalcurrentsuppliedtothedevice.Thedevicealsomighthavemorethanonepower
cord.Toremoveallelectricalcurrentfromthedevice,ensurethatallpowercordsaredisconnected
fromthepowersource.
1
2
CAUTION:
Donotplaceanyobjectweighingmorethan82kg(180lbs.)ontopofrack-mounteddevices.
8LenovoC540HardwareMaintenanceManual

Chapter3.Generalinformation
Thischapterprovidesgeneralinformationthatappliestoallcomputermodelscoveredbythismanual.
Specications
Thissectionliststhephysicalspecicationsforyourcomputer.
Thissectionliststhephysicalspecicationsforyourcomputer.
TypeLenovoC540
Thissectionliststhephysicalspecications.
Environment
Airtemperature:
Operating:10°to35°C
Transit:-20°to55°C
Humidity:
Operating:35%to80%
Transit:20%to90%(40°C)
Altitude:86KPato106KPa
Electricalinput:
Inputvoltage:90V-264V(AC)
Inputfrequency:47Hz-63Hz
©CopyrightLenovo20129

10LenovoC540HardwareMaintenanceManual

Chapter4.GeneralCheckout
Attention:Thedrivesinthecomputeryouareservicingmighthavebeenrearrangedorthedrivestartup
sequencemayhavebeenchanged.Beextremelycarefulduringwriteoperationssuchascopying,saving,or
formatting.Dataorprogramscanbeoverwrittenifyouselectanincorrectdrive.
Generalerrormessagesappearifaproblemorconictisfoundbyanapplication,theoperatingsystem,or
both.Foranexplanationofthesemessages,refertotheinformationsuppliedwiththatsoftwarepackage.
Usethefollowingproceduretohelpdeterminethecauseoftheproblem:
1.Power-offthecomputerandallexternaldevices.
2.Checkallcablesandpowercords.
3.Setalldisplaycontrolstothemiddleposition.
4.Power-onallexternaldevices.
5.Power-onthecomputer.
•Lookfordisplayederrorcodes.
•Lookforreadableinstructionsoramainmenuonthedisplay.
Ifyoudidnotreceivethecorrectresponse,proceedtostep6.
Ifyoudidreceivethecorrectresponse,proceedtostep7.
6.Ifoneofthefollowinghappens,followtheinstructiongiven:
•IfthecomputerdisplaysaPOSTerror,goto“POSTerrorcodes” .
•Ifthecomputerhangsandnoerrorisdisplayed,continueatstep7.
7.Iftheteststopsandyoucannotcontinue,replacethelastdevicetested.
©CopyrightLenovo201211

12LenovoC540HardwareMaintenanceManual

Chapter5.UsingtheSetupUtility
TheSetupUtilityprogramisusedtoviewandchangethecongurationsettingsofyourcomputer,regardless
ofwhichoperatingsystemyouareusing.However,theoperatingsystemsettingsmightoverrideanysimilar
settingsintheSetupUtilityprogram.
StartingtheLenovoBIOSSetupUtilityprogram
TostarttheLenovoBIOSSetupUtilityprogram,dothefollowing:
1.Ifyourcomputerisalreadyonwhenyoustartthisprocedure,shutdowntheoperatingsystemand
turnoffthecomputer.
2.PressandholdtheF1keythenturnonthecomputer.WhentheLenovoBIOSSetupUtilityprogramis
displayed,releasetheF1key.
Note:IfaPower-OnPasswordoranAdministratorPasswordhasbeenset,theSetupUtilityprogrammenu
willnotbedisplayeduntilyoutypeyourpassword.Formoreinformation,see“Usingpasswords.”
Viewingandchangingsettings
SystemcongurationoptionsarelistedintheLenovoBIOSSetupUtilityprogrammenu.Tovieworchange
settings,see“StartingtheSetupUtilityprogram.”
YoumustusethekeyboardwhenusingtheLenovoBIOSSetupUtilitymenu.Thekeysusedtoperform
varioustasksaredisplayedonthebottomofeachscreen.
Usingpasswords
YoucanusetheLenovoBIOSSetupUtilityprogramtosetpasswordstopreventunauthorizedpersons
fromgainingaccesstoyourcomputeranddata.See“StartingtheSetupUtilityprogram.”Thefollowing
typesofpasswordsareavailable:
•AdministratorPassword
•Power-OnPassword
Youdonothavetosetanypasswordstouseyourcomputer.However,ifyoudecidetosetpasswords,read
thefollowingsections.
Passwordconsiderations
Apasswordcanbeanycombinationoflettersandnumbersupto16characters(a-zand0-9).Forsecurity
reasons,itisagoodideatouseastrongpasswordthatcannotbeeasilycompromised.Wesuggestthat
passwordsshouldfollowtheserules:
•Forastrongpassword,use7-16charactersandamixoflettersandnumbers.
•Donotuseyournameoryourusername.
•Donotuseacommonwordoracommonname.
•Usesomethingsignicantlydifferentfromyourpreviouspassword.
Attention:AdministratorandPower-Onpasswordsarenotcasesensitive.
©CopyrightLenovo201213

AdministratorPassword
SettinganAdministratorPassworddetersunauthorizedpersonsfromchangingcongurationsettings.You
mightwanttosetanAdministratorPasswordifyouareresponsibleformaintainingthesettingsofseveral
computers.
AfteryousetanAdministratorPassword,apasswordpromptisdisplayedeverytimeyouaccesstheLenovo
BIOSSetupUtilityprogram.
IfboththeAdministratorandPower-OnPasswordareset,youcantypeeitherpassword.However,youmust
useyourAdministratorPasswordtochangeanycongurationsettings.
Setting,changing,ordeletinganAdministratorpassword
TosetanAdministratorPassword,dothefollowing:
Note:Apasswordcanbeanycombinationoflettersandnumbersupto16characters(a-zand0-9).For
moreinformation,see“Passwordconsiderations”onpage13.
1.StarttheLenovoBIOSSetupUtilityprogram(see“StartingtheLenovoBIOSSetupUtilityprogram”on
page13).
2.FromtheSecuritymenu,selectSetAdministratorPasswordandpresstheEnterkey.
3.Thepassworddialogboxwillbedisplayed.TypethepasswordthenpresstheEnterkey.
4.Re-typethepasswordtoconrm,thenpresstheEnterkey.Ifyoutypedthepasswordcorrectly,
thepasswordwillbeinstalled.
TochangeanAdministratorPassword,dothefollowing:
1.StarttheLenovoBIOSSetupUtilityprogram(see“StartingtheLenovoBIOSSetupUtilityprogram”on
page13).
2.FromtheSecuritymenu,selectSetAdministratorPasswordandpresstheEnterkey.
3.Thepassworddialogboxwillbedisplayed.TypethecurrentpasswordthenpresstheEnterkey.
4.Typethenewpassword,thenpresstheEnterkey.Re-typethepasswordtoconrmthenewpassword.
Ifyoutypedthenewpasswordcorrectly,thenewpasswordwillbeinstalled.ASetupNoticedconrming
thatchangeshavebeensavedwillbedisplayed.
TodeleteapreviouslysetAdministratorPassword,dothefollowing:
1.FromtheSecuritymenu,selectSetAdministratorPasswordandpresstheEnterkey.
2.Thepassworddialogboxwillbedisplayed.TypethecurrentpasswordandpresstheEnterkey.
3.TodeleteanAdministratorPassword,leaveeachnewpasswordlineitemblank,thenpresstheEnter
key.ASetupNoticeconrmingthatchangeshavebeensavedwillbedisplayed.
4.ReturntotheLenovoBIOSSetupUtilityprogrammenuandselecttheExitoption.
5.SelectSavechangesandExitfromthemenu.
Power-OnPassword
WhenaPower-OnPasswordisset,youcannotstarttheLenovoBIOSSetupUtilityprogramuntilavalid
passwordistypedfromthekeyboard.
Setting,changing,ordeletingaPower-OnPassword
Note:Apasswordcanbeanycombinationoflettersandnumbersupto16characters(a-zand0-9).
14LenovoC540HardwareMaintenanceManual