Lenovo ThinkPad T420, ThinkPad T420i Hardware Maintenance Manual

ThinkPadT420andT420i
HardwareMaintenanceManual

Note:Beforeusingthisinformationandtheproductitsupports,besuretoreadthegeneralinformation
underAppendixA“Notices”onpage175.

FifthEdition(March2012)

©CopyrightLenovo2012.

LIMITEDANDRESTRICTEDRIGHTSNOTICE:IfdataorsoftwareisdeliveredpursuantaGeneralServicesAdministration
“GSA”contract,use,reproduction,ordisclosureissubjecttorestrictionssetforthinContractNo.GS-35F-05925.

Contents

Aboutthismanual...........iii

Chapter1.Safetyinformation......1

Generalsafety................1

Electricalsafety...............2

Safetyinspectionguide............3

Handlingdevicesthataresensitivetoelectrostatic

discharge..................3

Groundingrequirements............4

Safetynotices(multilingualtranslations)......5

Lasercompliancestatement(multilingual

translations)................17

Chapter2.Importantservice

information..............23

StrategyforreplacingFRUs.........23

Strategyforreplacingaharddiskdrive...23
Importantnoticeforreplacingasystem

board................24

Howtouseerrormessage........24

StrategyforreplacingFRUsforCTO,CMV ,and

GAV...................25

Productdenition............25

FRUidenticationforCTO,CMV ,andGAV

products...............25

Chapter3.Generalcheckout.....27

Whattodorst..............28

Checkoutguide..............29

SystemsupportingtheLenovoThinkVantage
ToolboxprogramandthePC-DoctorforDOS

diagnosticsprogram..........29

SystemsupportingtheLenovodiagnostics

programs...............33

Powersystemcheckout...........37

Checkingtheacpoweradapter......37

Checkingoperationalcharging......37

Checkingthebatterypack........38

Checkingthebackupbattery.......38

Chapter4.Relatedservice

information..............41

RestoringthefactorycontentsbyusingRecovery

DiscSet.................41

Passwords................42

Power-onpassword...........42

Hard-diskpassword...........42

Supervisorpassword..........43

Howtoremovethepower-onpassword...43

Howtoremovethehard-diskpassword...43

Powermanagement............45

Screenblankmode...........45

Sleep(standby)mode..........45

Hibernationmode...........45

Symptom-to-FRUindex...........47

Numericerrorcodes..........47

Errormessages............49

Beepsymptoms............50

No-beepsymptoms...........50

LCD-relatedsymptoms.........50

Intermittentproblems..........52

Undeterminedproblems.........52

Chapter5.Statusindicators.....53

Chapter6.Fnkeycombinations...57

Chapter7.FRUreplacement

notices................61

Screwnotices...............61

Retainingserialnumbers...........62

Restoringtheserialnumberofthesystem

unit.................62

RetainingtheUUID...........63

ReadingorwritingtheECAinformation...63

Chapter8.Removingandreplacinga

FRU..................65

BeforeservicingThinkPadT420andT420i...66

1010Batterypack.............67

1020ExpressCardblankbezel........68

1030SerialUltrabayEnhanceddeviceortravel

bezel..................69

1040Harddiskdrive(HDD)andsolidstatedrive

(SSD)..................70

1050DIMMslotcover............73

1060DIMM(intheslotontheundersideofthe

computer)................74

1070PCIExpressMiniCardforwirelessWAN..75

1080Keyboard..............77

1090DIMM(intheslotunderthekeyboard)...81

1100Backupbattery............83

1110PCIExpressMiniCardforwirelessLAN..85
1120Keyboardbezelassembly,FPCcable,and

Bluethoothdaughtercard..........87

1130SmartCard..............92

1140Modemdaughtercard(MDC).......94

©CopyrightLenovo2012

i

1150Speakerassembly...........95

1160LCDunit...............97

1170Fanassembly.............101

1180CPU................105

1190BasecoverassemblyandDC-inconnector

cable..................106

1200Magnesiumstructureframe.......110

1210SystemboardandExpressCardslot

assembly.................112

1220mSATAsolidstatedrive.........114

2010LCDbezelassembly..........116

2020LEDboard..............117

2030Integratedcamera...........119

2040LCDpanelandLCDcable........121

2050Cameracable.............123

2060WirelessLANantennaassemblyorwireless

LAN/WANantennaassembly.........124

2070HingesandLCDrearcoverassembly...126

Chapter9.Locations........129

Frontview................129

Rearview.................131

Bottomview...............132

Chapter10.Partslist........133

Overall..................134

LCDFRUs................155

Keyboard.................160

Miscellaneousparts............162

Informationaboutacpoweradapters......164

Powercords...............165

Recoverydiscs..............166

Commonservicetools...........173

AppendixA.Notices.........175

Electronicemissionsnotices.........176

Trademarks................177

iiThinkPadT420andT420iHardwareMaintenanceManual

Aboutthismanual

ThismanualcontainsserviceandreferenceinformationforthefollowingThinkPad

®

products.

ThinkPadT420andT420iMachineType4177,4178,4179,4180,4236,4237,and4238

Usethismanualalongwiththeadvanceddiagnosticteststotroubleshootproblems.

Important:

ThismanualisintendedonlyfortrainedservicetechnicianswhoarefamiliarwithThinkPadproducts.Usethis
manualalongwiththeadvanceddiagnosticteststotroubleshootproblemseffectively.
BeforeservicingaThinkPadproduct,besuretoreadalltheinformationunderChapter1“Safetyinformation”on
page1andChapter2“Importantserviceinformation”onpage23.

©CopyrightLenovo2012

iii

ivThinkPadT420andT420iHardwareMaintenanceManual

Chapter1.Safetyinformation

Thischapterpresentsfollowingsafetyinformationthatyouneedtobefamiliarwithbeforeyouservice
aThinkPadNotebook.

•“Generalsafety”onpage1

•“Electricalsafety”onpage2

•“Safetyinspectionguide”onpage3

•“Handlingdevicesthataresensitivetoelectrostaticdischarge”onpage3

•“Groundingrequirements”onpage4

•“Safetynotices(multilingualtranslations)”onpage5

•“Lasercompliancestatement(multilingualtranslations)”onpage17

Generalsafety

Followtheserulestoensuregeneralsafety:

•Observegoodhousekeepingintheareaofthemachinesduringandaftermaintenance.

•Whenliftinganyheavyobject:

1.Makesurethatyoucanstandsafelywithoutslipping.

2.Distributetheweightoftheobjectequallybetweenyourfeet.

3.Useaslowliftingforce.Nevermovesuddenlyortwistwhenyouattempttolift.

4.Liftbystandingorbypushingupwithyourlegmuscles;thisactionremovesthestrainfromthe
musclesinyourback.Donotattempttoliftanyobjectthatweighsmorethan16kg(35lb)orthat

youthinkistooheavyforyou.

•Donotperformanyactionthatcauseshazardstothecustomer,orthatmakestheequipmentunsafe.

•Beforeyoustartthemachine,makesurethatotherservicetechniciansandthecustomer'spersonnelare
notinahazardousposition.

•Placeremovedcoversandotherpartsinasafeplace,awayfromallpersonnel,whileyouareservicing
themachine.

•Keepyourtoolcaseawayfromwalkareassothatotherpeoplewillnottripoverit.

•Donotwearlooseclothingthatcanbetrappedinthemovingpartsofamachine.Makesurethatyour
sleevesarefastenedorrolledupaboveyourelbows.Ifyourhairislong,fastenit.

•Inserttheendsofyournecktieorscarfinsideclothingorfastenitwithanonconductiveclip,about8
centimeters(3inches)fromtheend.

•Donotwearjewelry,chains,metal-frameeyeglasses,ormetalfastenersforyourclothing.

Attention:Metalobjectsaregoodelectricalconductors.

•Wearsafetyglasseswhenyouarehammering,drilling,soldering,cuttingwire,attachingsprings,using
solvents,orworkinginanyotherconditionsthatmightbehazardoustoyoureyes.

•Afterservice,reinstallallsafetyshields,guards,labels,andgroundwires.Replaceanysafetydevice
thatiswornordefective.

•Reinstallallcoverscorrectlybeforereturningthemachinetothecustomer.

•Fanlouversonthemachinehelptopreventoverheatingofinternalcomponents.Donotobstructfan
louversorcoverthemwithlabelsorstickers.

©CopyrightLenovo2012

1

Electricalsafety

Observethefollowingruleswhenworkingonelectricalequipment.

Important:

Useonlyapprovedtoolsandtestequipment.Somehandtoolshavehandlescoveredwithasoftmaterialthatdoes
notinsulateyouwhenworkingwithliveelectricalcurrents.
Manycustomershave,neartheirequipment,rubberoormatsthatcontainsmallconductiveberstodecrease
electrostaticdischarges.Donotusethistypeofmattoprotectyourselffromelectricalshock.

•Findtheroomemergencypower-off(EPO)switch,disconnectingswitch,orelectricaloutlet.Ifanelectrical
accidentoccurs,youcanthenoperatetheswitchorunplugthepowercordquickly.

•Donotworkaloneunderhazardousconditionsornearequipmentthathashazardousvoltages.

•Disconnectallpowerbefore:
–Performingamechanicalinspection
–Workingnearpowersupplies
–Removingorinstallingmainunits

•Beforeyoustarttoworkonthemachine,unplugthepowercord.Ifyoucannotunplugit,askthecustomer
topower-offthewallboxthatsuppliespowertothemachine,andtolockthewallboxintheoffposition.

•Ifyouneedtoworkonamachinethathasexposedelectricalcircuits,observethefollowingprecautions:
–Ensurethatanotherperson,familiarwiththepower-offcontrols,isnearyou.

Attention:Anotherpersonmustbetheretoswitchoffthepower,ifnecessary.

–Useonlyonehandwhenworkingwithpowered-onelectricalequipment;keeptheotherhandinyour

pocketorbehindyourback.

Attention:Anelectricalshockcanoccuronlywhenthereisacompletecircuit.Byobservingtheabove
rule,youmaypreventacurrentfrompassingthroughyourbody.

–Whenusingtesters,setthecontrolscorrectlyandusetheapprovedprobeleadsandaccessoriesfor

thattester.

–Standonsuitablerubbermats(obtainedlocally,ifnecessary)toinsulateyoufromgroundssuchas

metaloorstripsandmachineframes.
Observethespecialsafetyprecautionswhenyouworkwithveryhighvoltages;Instructionsforthese
precautionsareinthesafetysectionsofmaintenanceinformation.Useextremecarewhenmeasuring
highvoltages.

•Regularlyinspectandmaintainyourelectricalhandtoolsforsafeoperationalcondition.

•Donotusewornorbrokentoolsandtesters.

•Neverassumethatpowerhasbeendisconnectedfromacircuit.First,checkthatithasbeenpoweredoff.

•Alwayslookcarefullyforpossiblehazardsinyourworkarea.Examplesofthesehazardsaremoistoors,
nongroundedpowerextensioncables,powersurges,andmissingsafetygrounds.

•Donottouchliveelectricalcircuitswiththereectivesurfaceofaplasticdentalmirror.Thesurfaceis
conductive;suchtouchingcancausepersonalinjuryandmachinedamage.

•Donotservicethefollowingpartswiththepoweronwhentheyareremovedfromtheirnormaloperating
placesinamachine:
–Powersupplyunits
–Pumps
–Blowersandfans
–Motorgenerators
–Similarunitstolistedabove
Thispracticeensurescorrectgroundingoftheunits.

•Ifanelectricalaccidentoccurs:

2ThinkPadT420andT420iHardwareMaintenanceManual

–Usecaution;donotbecomeavictimyourself.
–Switchoffpower.
–Sendanotherpersontogetmedicalaid.

Safetyinspectionguide

Thepurposeofthisinspectionguideistoassistyouinidentifyingpotentiallyunsafeconditions.Aseach
machinewasdesignedandbuilt,requiredsafetyitemswereinstalledtoprotectusersandservicetechnicians
frominjury.Thisguideaddressesonlythoseitems.Y oushouldusegoodjudgmenttoidentifypotential
safetyhazardsduetoattachmentofnon- ThinkPadfeaturesoroptionsnotcoveredbythisinspectionguide.

Ifanyunsafeconditionsarepresent,youmustdeterminehowserioustheapparenthazardcouldbeand
whetheryoucancontinuewithoutrstcorrectingtheproblem.

Considertheseconditionsandthesafetyhazardstheypresent:

•Electricalhazards,especiallyprimarypower(primaryvoltageontheframecancauseseriousorfatal
electricalshock)

•Explosivehazards,suchasadamagedCRTfaceorabulgingcapacitor

•Mechanicalhazards,suchaslooseormissinghardware

Todeterminewhetherthereareanypotentiallyunsafeconditions,usethefollowingchecklistatthebeginning
ofeveryservicetask.Beginthecheckswiththepoweroff,andthepowercorddisconnected.

Checklist:

1.Checkexteriorcoversfordamage(loose,broken,orsharpedges).

2.Poweroffthecomputer.Disconnectthepowercord.

3.Checkthepowercordfor:

a.Athird-wiregroundconnectoringoodcondition.Useametertomeasurethird-wireground

continuityfor0.1ohmorlessbetweentheexternalgroundpinandtheframeground.

b.Thepowercordshouldbethetypespeciedinthepartslist.

c.Insulationmustnotbefrayedorworn.

4.Checkforcrackedorbulgingbatteries.

5.Removethecover.

6.Checkforanyobviousnon- ThinkPadalterations.Usegoodjudgmentastothesafetyofany
non-ThinkPadalterations.

7.Checkinsidetheunitforanyobviousunsafeconditions,suchasmetallings,contamination,wateror
otherliquids,orsignsofreorsmokedamage.

8.Checkforworn,frayed,orpinchedcables.

9.Checkthatthepower-supplycoverfasteners(screwsorrivets)havenotbeenremovedortamperedwith.

Handlingdevicesthataresensitivetoelectrostaticdischarge

Anycomputerpartcontainingtransistorsorintegratedcircuits(ICs)shouldbeconsideredsensitiveto
electrostaticdischarge(ESD).ESDdamagecanoccurwhenthereisadifferenceinchargebetweenobjects.
ProtectagainstESDdamagebyequalizingthechargesothatthemachine,thepart,theworkmat,andthe
personhandlingthepartareallatthesamecharge.

Chapter1.Safetyinformation3

Notes:

1.Useproduct-specicESDprocedureswhentheyexceedtherequirementsnotedhere.

2.MakesurethattheESDprotectivedevicesyouusehavebeencertied(ISO9000)asfullyeffective.

WhenhandlingESD-sensitiveparts:

•Keepthepartsinprotectivepackagesuntiltheyareinsertedintotheproduct.

•Avoidcontactwithotherpeople.

•Wearagroundedwriststrapagainstyourskintoeliminatestaticonyourbody.

•Preventthepartfromtouchingyourclothing.Mostclothingisinsulativeandretainsachargeevenwhen
youarewearingawriststrap.

•Useagroundedworkmattoprovideastatic-freeworksurface.Thematisespeciallyusefulwhen
handlingESD-sensitivedevices.

•Selectagroundingsystem,suchasthoselistedbelow,toprovideprotectionthatmeetsthespecic
servicerequirement.

Note:TheuseofagroundingsystemtoguardagainstESDdamageisdesirablebutnotnecessary.

–AttachtheESDgroundcliptoanyframeground,groundbraid,orgreen-wireground.

–Whenworkingonadouble-insulatedorbattery-operatedsystem,useanESDcommongroundor

referencepoint.Y oucanusecoaxorconnector-outsideshellsonthesesystems.

–Usetheroundgroundprongoftheacplugonac-operatedcomputers.

Groundingrequirements

Electricalgroundingofthecomputerisrequiredforoperatorsafetyandcorrectsystemfunction.Proper
groundingoftheelectricaloutletcanbeveriedbyacertiedelectrician.

4ThinkPadT420andT420iHardwareMaintenanceManual

Safetynotices(multilingualtranslations)

Thesafetynoticesinthissectionareprovidedinthefollowinglanguages:

•English

•Arabic

•BrazilianPortuguese

•French

•German

•Hebrew

•Japanese

•Korean

•Spanish

•T raditionalChinese

DANGER

BeforethecomputerispoweredonafterFRUreplacement,makesureallscrews,springs,andothersmall
partsareinplaceandarenotleftlooseinsidethecomputer.Verifythisbyshakingthecomputerandlistening
forrattlingsounds.Metallicpartsormetalakescancauseelectricalshorts.

DANGER

Somestandbybatteriescontainasmallamountofnickelandcadmium.Donotdisassembleastandbybattery,
rechargeit,throwitintoreorwater,orshort-circuitit.Disposeofthebatteryasrequiredbylocalordinances
orregulations.Useonlythebatteryintheappropriatepartslisting.Useofanincorrectbatterycanresult
inignitionorexplosionofthebattery.

DANGER

Thebatterypackcontainssmallamountsofnickel.Donotdisassembleit,throwitintoreorwater ,or
short-circuitit.Disposeofthebatterypackasrequiredbylocalordinancesorregulations.Useonlythe
batteryintheappropriatepartslistingwhenreplacingthebatterypack.Useofanincorrectbatterycanresult
inignitionorexplosionofthebattery.

DANGER

Thelithiumbatterycancauseare,anexplosion,orasevereburn.Donotrechargeit,removeitspolarized
connector,disassembleit,heatitabove100°C(212°F),incinerateit,orexposeitscellcontentstowater.
Disposeofthebatteryasrequiredbylocalordinancesorregulations.Useonlythebatteryintheappropriate
partslisting.Useofanincorrectbatterycanresultinignitionorexplosionofthebattery.

Chapter1.Safetyinformation5

DANGER

IftheLCDbreaksandtheuidfrominsidetheLCDgetsintoyoureyesoronyourhands,immediatelywash
theaffectedareaswithwaterforatleast15minutes.Seekmedicalcareifanysymptomsfromtheuidare
presentafterwashing.

DANGER

Toavoidshock,donotremovetheplasticcoverthatprotectsthelowerpartoftheinvertercard.

DANGER

Thoughthemainbatterieshavelowvoltage,ashortedorgroundedbatterycanproduceenoughcurrentto
burnpersonnelorcombustiblematerials.

DANGER

UnlesshotswapisallowedfortheFRUbeingreplaced,doasfollowsbeforeremovingit:poweroffthe
computer,unplugallpowercordsfromelectricaloutlets,removethebatterypack,anddisconnectany
interconnectingcables.

6ThinkPadT420andT420iHardwareMaintenanceManual

PERIGO

Chapter1.Safetyinformation7

AntesdeligarocomputadorapósasubstituiçãodaFRU,certique-sedequetodososparafusos,molase
outraspeçaspequenasestejamnolugarenãoestejamsoltosdentrodocomputador.Veriqueissosacudindo
ocomputadoreprocurandoouvirsonsdepeçassoltas.Peçasmetálicasoulascasdemetalpodemcausar
curto-circuito.

PERIGO

Algumasbateriasreservacontêmumapequenaquantidadedeníquelecádmio.Nãodesmonteumabateria
reserva,recarregue-a,jogue-anofogoounaágua,oudeixe-aentraremcurto-circuito.Descarteabateria
conformerequeridopelasleisouregulamentoslocais.Usesomenteabaterianasparteslistadasapropriadas.
Ousodeumabateriaincorretapoderesultaremcombustãoouexplosãodabateria.

PERIGO

Opacotedabateriacontémumapequenaquantidadedeníquel.Nãoodesmonte,jogue-onofogoouna
água,oudeixe-oentraremcurto-circuito.Descarteopacotedabateriaconformerequeridopelasleisou
regulamentoslocais.Usesomenteabaterianasparteslistadasapropriadasaosubstituiropacotedabateria.
Ousodeumabateriaincorretapoderesultaremcombustãoouexplosãodabateria.

PERIGO

Abateriadelítiopodecausarincêndio,explosãoougravesqueimaduras.Nãoarecarregue,removaseu
conectorpolarizado,desmonte-a,aqueça-aacimade100°C(212°F),incinere-a,ouexponhaoconteúdode
suacélulaàágua.Descarteabateriaconformerequeridopelasleisouregulamentoslocais.Usesomente
abaterianasparteslistadasapropriadas.Ousodeumabateriaincorretapoderesultaremcombustão
ouexplosãodabateria.

PERIGO

SeoLCDquebrareouidodedentrodeleentraremcontatocomseusolhosoucomsuasmãos,laveas
áreasafetadasimediatamentecomáguadurantepelomenos15minutos.Procurecuidadosmédicossealgum
sintomacausadopelouidosurgirapósalavagem.

PERIGO

Paraevitarchoqueelétrico,nãoremovaacapaplásticaqueprotegeaparteinferiordaplacainversora.

PERIGO

8ThinkPadT420andT420iHardwareMaintenanceManual

Emboraasprincipaisbateriaspossuambaixavoltagem,umabateriaemcurto-circuitoouaterradapode
produzircorrenteobastanteparaqueimarmateriaisdepessoalouinamáveis.

PERIGO

AmenosqueumahotswapsejapermitidaparaaFRUqueestásendosubstituída,façaoseguinteantesde
removê-la:desligueocomputador,desconectetodososcabosdeenergiadastomadas,removaopacotede
bateriasedesconectequaisquercabosdeinterconexão.

DANGER

Avantderemettrel'ordinateursoustensionaprèsremplacementd'uneunitéenclientèle,vériezquetousles
ressorts,visetautrespiècessontbienenplaceetbienxées.Pourcefaire,secouezl'unitéetassurez-vous
qu'aucunbruitsuspectneseproduit.Despiècesmétalliquesoudescopeauxdemétalpourraientcauser
uncourt-circuit.

DANGER

Certainesbatteriesdesecourscontiennentdunickeletducadmium.Nelesdémontezpas,nelesrechargez
pas,nelesexposezniaufeuniàl'eau.Nelesmettezpasencourt-circuit.Pourlesmettreaurebut,
conformez-vousàlaréglementationenvigueur.Lorsquevousremplacezlapiledesauvegardeoucellede
l'horlogetempsréel,veillezàn'utiliserquelesmodèlescitésdanslalistedepiècesdétachéesadéquate.Une
batterieouunepileinappropriéerisquedeprendrefeuoud'exploser.

DANGER

Labatteriecontientdunickel.Neladémontezpas,nel'exposezniaufeuniàl'eau.Nelamettezpasen
court-circuit.Pourlamettreaurebut,conformez-vousàlaréglementationenvigueur.Lorsquevousremplacez
labatterie,veillezàn'utiliserquelesmodèlescitésdanslalistedepiècesdétachéesadéquate.Eneffet,une
batterieinappropriéerisquedeprendrefeuoud'exploser.

DANGER

Lapiledesauvegardecontientdulithium.Elleprésentedesrisquesd'incendie,d'explosionoudebrûlures
graves.Nelarechargezpas,neretirezpassonconnecteurpolariséetneladémontezpas.Nel'exposezpasà
unetemperaturesupérieureà100°C,nelafaitespasbrûleretn'enexposezpaslecontenuàl'eau.Mettezla
pileaurebutconformémentàlaréglementationenvigueur.Unepileinappropriéerisquedeprendrefeuou
d'exploser.

Chapter1.Safetyinformation9

DANGER

Silepanneaud'afchageàcristauxliquidessebriseetquevousrecevezdanslesyeuxousurlesmainsune
partieduuide,rincez-lesabondammentpendantaumoinsquinzeminutes.Consultezunmédecinsides
symptômespersistentaprèslelavage.

DANGER

And'évitertoutrisquedechocélectrique,neretirezpaslecacheenplastiqueprotégeantlapartieinférieure
delacarted'alimentation.

DANGER

Bienquelevoltagedesbatteriesprincipalessoitpeuélevé,lecourt-circuitoulamiseàlamassed'une
batteriepeutproduiresufsammentdecourantpourbrûlerdesmatériauxcombustiblesoucauserdes
brûlurescorporellesgraves.

DANGER

Sileremplacementàchaudn'estpasautorisépourl'unitéremplaçablesursitequevousremplacez,
procédezcommesuitavantderetirerl'unité:mettezl'ordinateurhorstension,débrancheztousles
cordonsd'alimentationdesprisesdecourant,retirezleblocdebatterieetdéconnecteztouslescâbles
d'interconnexion.

VORSICHT

BevornacheinemFRU-AustauschderComputerwiederangeschlossenwird,mußsichergestelltwerden,daß
keineSchrauben,FedernoderandereKleinteilefehlenoderimGehäusevergessenwurden.DerComputermuß
geschütteltundaufKlappergeräuschegeprüftwerden.Metallteileoder-splitterkönnenKurzschlüsseerzeugen.

VORSICHT

DieBereitschaftsbatterie,diesichunterdemDiskettenlaufwerkbendet,kanngeringeMengenNickel
undCadmiumenthalten.SiedarfnurdurchdieVerkaufsstelleoderdenIBMKundendienstausgetauscht
werden.Siedarfnichtzerlegt,wiederaufgeladen,kurzgeschlossen,oderFeueroderWasserausgesetzt
werden.DieBatteriekannschwereVerbrennungenoderVerätzungenverursachen.BeiderEntsorgungdie
örtlichenBestimmungenfürSondermüllbeachten.BeimErsetzenderBereitschafts-oderSystembatterienur
BatteriendesTypsverwenden,derinderErsatzteillisteaufgeführtist.DerEinsatzfalscherBatterienkann
zuEntzündungoderExplosionführen.

10ThinkPadT420andT420iHardwareMaintenanceManual

VORSICHT

AkkusenthaltengeringeMengenvonNickel.Siedürfennichtzerlegt,wiederaufgeladen,kurzgeschlossen,
oderFeueroderWasserausgesetztwerden.BeiderEntsorgungdieörtlichenBestimmungenfürSondermüll
beachten.BeimErsetzenderBatterienurBatteriendesT ypsverwenden,derinderErsatzteillisteaufgeführt
ist.DerEinsatzfalscherBatterienkannzuEntzündungoderExplosionführen.

VORSICHT

DieSystembatterieisteineLithiumbatterie.Siekannsichentzünden,explodierenoderschwereVerbrennungen
hervorrufen.BatteriendiesesT ypsdürfennichtaufgeladen,zerlegt,über100°Cerhitztoderverbranntwerden.
AuchdarfihrInhaltnichtmitWasserinVerbindunggebrachtoderderzurrichtigenPolungangebrachte
Verbindungssteckerentferntwerden.BeiderEntsorgungdieörtlichenBestimmungenfürSondermüll
beachten.BeimErsetzenderBatterienurBatteriendesT ypsverwenden,derinderErsatzteillisteaufgeführt
ist.DerEinsatzfalscherBatterienkannzuEntzündungoderExplosionführen.

VORSICHT

DieLeuchtstoffröhreimLCD-BildschirmenthältQuecksilber .BeiderEntsorgungdieörtlichenBestimmungen
fürSondermüllbeachten.DerLCD-BildschirmbestehtausGlasundkannzerbrechen,wennerunsachgemäß
behandeltwirdoderderComputeraufdenBodenfällt.WennderBildschirmbeschädigtistunddiedarin
bendlicheFlüssigkeitinKontaktmitHautundAugengerät,solltendiebetroffenenStellenmindestens15
MinutenmitWasserabgespültundbeiBeschwerdenanschließendeinArztaufgesuchtwerden.

VORSICHT

AusSicherheitsgründendieKunststoffabdeckung,diedenunterenT eilderSpannungswandlerplatineumgibt,
nichtentfernen.

VORSICHT

ObwohlHauptbatterieneineniedrigeSpannunghaben,könnensiedochbeiKurzschlußoderErdunggenug
Stromabgeben,umbrennbareMaterialienzuentzündenoderVerletzungenbeiPersonenhervorzurufen.

VORSICHT

Chapter1.Safetyinformation11

WenneinAustauschderFRUbeilaufendemBetriebnichterlaubtist,gehenSiebeimAustauschderFRUwie
folgtvor:SchaltenSiedenComputeraus,ziehenSiealleNetzkabelvondenNetzsteckdosenab,entfernen
SiedenAkkuundziehenSieallemiteinanderverbundenenKabelab.

12ThinkPadT420andT420iHardwareMaintenanceManual

Chapter1.Safetyinformation13

14ThinkPadT420andT420iHardwareMaintenanceManual

AntesdeencenderelsistemadespuesdesustituirunaFRU,compruebequetodoslostornillos,muellesy
demáspiezaspequeñasseencuentranensusitioynoseencuentransueltasdentrodelsistema.Compruébelo
agitandoelsistemayescuchandolosposiblesruidosqueprovocarían.Laspiezasmetálicaspuedencausar
cortocircuitoseléctricos.

Algunasbateríasdereservacontienenunapequeñacantidaddeníquelycadmio.Nolasdesmonte,ni
recargue,nilasechealfuegooalaguanilascortocircuite.Deséchelastalcomodisponelanormativalocal.
Utilicesólobateríasqueseencuentrenenlalistadepiezas.Lautilizacióndeunabateríanoapropiada
puedeprovocarlaigniciónoexplosióndelamisma.

Lasbateríascontienenpequeñascantidadesdeníquel.Nolasdesmonte,nirecargue,nilasechealfuego
oalaguanilascortocircuite.Deséchelastalcomodisponelanormativalocal.Utilicesólobateríasquese
encuentrenenlalistadepiezasalsustituirlabatería.Lautilizacióndeunabateríanoapropiadapuede
provocarlaigniciónoexplosióndelamisma.

Labateríaderepuestoesunabateríadelitioypuedeprovocarincendios,explosionesoquemadurasgraves.
Nolarecargue,niquiteelconectorpolarizado,niladesmonte,nicalienteporencimadelos100°C(212°F),ni
laincinereniexpongaelcontenidodesusceldasalagua.Deséchelatalcomodisponelanormativalocal.

SilaLCDserompeyeluidodesuinteriorentraencontactoconsusojososusmanos,laveinmediatamente
lasáreasafectadasconaguadurante15minutoscomomínimo.Obtengaatenciónmedicasisepresenta
algúnsíntomadeluidodespuesdelavarse.

Chapter1.Safetyinformation15

Paraevitardescargas,noquitelacubiertadeplásticoquerodealapartebajadelatarjetainvertida.

Aunquelasbateríasprincipalestienenunvoltajebajo,unabateríacortocircuitadaoconcontactoatierra
puedeproducirlacorrientesucientecomoparaquemarmaterialcombustibleoprovocarquemadurasen
elpersonal.

Salvoquesepermitaelintercambioencalienteparalaunidadsustituiblelocalmente,realicelosiguienteantes
deextraerla:apagueelsistema,desconectetodosloscablesdealimentacióndelastomasdealimentación
eléctrica,extraigalabateríaydesconecteloscablesdeinterconexión.

16ThinkPadT420andT420iHardwareMaintenanceManual

Lasercompliancestatement(multilingualtranslations)

Thelasercompliancestatementsinthissectionareprovidedinthefollowinglanguages:

•English

•Arabic

•BrazilianPortuguese

•French

•German

•Hebrew

•Japanese

•Korean

•Spanish

•T raditionalChinese

Chapter1.Safetyinformation17

18ThinkPadT420andT420iHardwareMaintenanceManual

Chapter1.Safetyinformation19

20ThinkPadT420andT420iHardwareMaintenanceManual

Chapter1.Safetyinformation21

22ThinkPadT420andT420iHardwareMaintenanceManual

Chapter2.Importantserviceinformation

Thischapterpresentsfollowingimportantserviceinformationthatappliestoallmachinetypessupportedby
thismanual:

•“StrategyforreplacingFRUs”onpage23
–“Strategyforreplacingaharddiskdrive”onpage23
–“Importantnoticeforreplacingasystemboard”onpage24
–“Howtouseerrormessage”onpage24

•“StrategyforreplacingFRUsforCTO,CMV,andGAV”onpage25
–“Productdenition”onpage25
–“FRUidenticationforCTO,CMV ,andGAVproducts”onpage25

Important:

AdvisecustomerstocontacttheLenovoCustomerSupportCenteriftheyneedanyassistanceinobtainingor
installinganysoftwarexes,drivers,andUEFIBIOSdownloads.TelephonenumbersforLenovoSupportare
availableathttp://www.lenovo.com/support.
SystemDisassembly/ReassemblyvideosthatshowtheFRUremovalsorreplacementsfortheLenovo
servicetechniciansareavailableinthefollowingsupportsite:
http://www.lenovoservicetraining.com/ion/

StrategyforreplacingFRUs

Beforereplacingparts:

Makesurethatallsoftwarexes,drivers,andUEFIBIOSdownloadsareinstalledbeforereplacingany
FRUslistedinthismanual.

®

authorized

Afterasystemboardisreplaced,ensurethatthelatestUEFIBIOSisloadedtothesystemboardbefore
completingtheserviceaction.

Todownloadsoftwarexes,drivers,andUEFIBIOS,gotohttp://www.lenovo.com/supportandclick
DownloadDrivers&Software.Thenfollowtheinstructionsonthescreentoinstallthenecessarysoftware.

UsethefollowingstrategytopreventunnecessaryexpenseforreplacingandservicingFRUs:

•IfyouareinstructedtoreplaceaFRUbutthereplacementdoesnotcorrecttheproblem,reinstall
theoriginalFRUbeforeyoucontinue.

•Somecomputershavebothaprocessorboardandasystemboard.Ifyouareinstructedtoreplaceeither
theprocessorboardorthesystemboard,andreplacingoneofthemdoesnotcorrecttheproblem,
reinstallthatboard,andthenreplacetheotherone.

•IfanadapteroradeviceconsistsofmorethanoneFRU,anyoftheFRUsmaybethecauseoftheerror.
Beforereplacingtheadapterordevice,removetheFRUs,onebyone,toseeifthesymptomschange.
ReplaceonlytheFRUthatchangedthesymptoms.

Attention:Thesetupcongurationonthecomputeryouareservicingmayhavebeencustomized.Running
AutomaticCongurationmayalterthesettings.Notethecurrentcongurationsettings(usingtheView
Congurationoption);then,whenservicehasbeencompleted,verifythatthosesettingsremainineffect.

Strategyforreplacingaharddiskdrive

Alwaystrytorunalow-levelformatbeforereplacingaharddiskdrive.Thiswillcauseallcustomerdataon
theharddisktobelost.Besurethatthecustomerhasacurrentbackupofthedatabeforedoingthistask.

©CopyrightLenovo2012

23

Attention:Thedrivestartupsequenceinthecomputeryouareservicingmayhavebeenchanged.Be

extremelycarefulduringwriteoperationssuchascopying,saving,orformatting.Ifyouselectanincorrect
drive,dataorprogramscanbeoverwritten.

IfyourcomputerisshippedwithanmSATAdriveandasolidstatedriveorharddiskdrive,themSA T Adrive
willbeseenasharddisk0inthesystem,andassigneddriveC:.Thesolidstatedriveorharddiskdrivewill
beseenasharddisk1,andassigneddriveD:.ThemSATAdriveisinstalledinthewirelessWANcardslotof
thecomputer.TheLenovopreloadedsoftwareisinstalledonthemSATAdrive.

Alwaystrytorunalow-levelformatbeforereplacingaharddiskdrive.Thiswillcauseallcustomerdataon
theharddisktobelost.Besurethatthecustomerhasacurrentbackupofthedatabeforedoingthistask.

Attention:Thedrivestartupsequenceinthecomputeryouareservicingmayhavebeenchanged.Be
extremelycarefulduringwriteoperationssuchascopying,saving,orformatting.Ifyouselectanincorrect
drive,dataorprogramscanbeoverwritten.

Importantnoticeforreplacingasystemboard

Somecomponentsmountedonasystemboardareverysensitive.Improperhandlingofasystemboardcan
causedamagetothosecomponents,andmaycauseasystemmalfunction.

Attention:Whenhandlingasystemboard:

•Donotdropasystemboardorapplyanyexcessiveforcetoit.

•Avoidroughhandlingofanykind.

•AvoidbendingasystemboardandhardpushingtopreventcrackingateachBGA(BallGridArray)chipset.

Howtouseerrormessage

Usetheerrorcodesdisplayedonthescreentodiagnosefailures.Ifmorethanoneerrorcodeisdisplayed,
beginthediagnosiswiththersterrorcode.Whatevercausesthersterrorcodemayalsocausefalseerror
codes.Ifnoerrorcodeisdisplayed,seewhethertheerrorsymptomislistedintheSymptom-to-FRU
Indexforthecomputeryouareservicing.

24ThinkPadT420andT420iHardwareMaintenanceManual

StrategyforreplacingFRUsforCTO,CMV,andGAV

Productdenition

DynamicCongureT oOrder(CTO)

ThisprovidestheabilityforacustomertocongureaLenovosolutionfromaneSite,andhavethis
congurationsenttofulllment,whereitisbuiltandshippeddirectlytothecustomer.Themachinelabel,
ProductEntitlementWarehouse(PEW),eSupport,andtheHMMwillloadtheseproductsasthe4-digitMT
and3-digitmodel,wheremodel=“CTO”(Example:1829-CTO).

CustomModelVariant(CMV)

ThisisauniquecongurationthathasbeennegotiatedbetweenLenovoandthecustomer.Aunique4-digit
MTand3-digitmodelisprovidedtothecustomertoplaceorders(Example:1829-W15).ACMVisaspecial
bidoffering.Therefore,itisNOTgenerallyannounced.

•TheMTMportionofthemachinelabelisthe4-digitMTand3-digitmodel,wheremodel=“CTO”
(Example:1829-CTO).ThePRODUCTIDportionofthemachinelabelisthe4-digitMTand3-digitCMV
model(Example:1829-W15).

•ThePEWrecordisthe4-digitMTand3-digitmodel,wheremodel=“CTO”(Example:1829-CTO).

•eSupportwillshowboththeCTOandCMVmachinetypemodels(Example:1829-CTOand1829-W15
willbefoundontheeSupportsite.)

•TheHMMwillhavethe4-digitMTand3-digitCTOmodelonly(Example:1829-CTO).Again,CMVsare
custommodelsandarenotfoundintheHMM.

GeneralAnnounceVariant(GAV)

Thisisastandardmodel(xedconguration).GAVsareannouncedandofferedtoallcustomers.TheMTM
portionofthemachinelabelisa4-digitMTand3-digitmodel,wheremodel=a“xedpartnumber”,not
“CTO”(Example:1829-F1U).Also,PEW,eSupport,andtheHMMwilllisttheseproductsunderthesame
xedmodelnumber.

FRUidenticationforCTO,CMV,andGAVproducts

TherearethreeinformationresourcestoidentifywhichFRUsareusedtosupportCTO,CMV,andGAV
products.ThesesourcesarePEW,eSupport,andtheHMM.

UsingPEW

•PEWistheprimarysourceforidentifyingFRUpartnumbersandFRUdescriptionsforthekeycommodities
forCTO,CMVandGAVproductsataMT-serialnumberlevel.Anexampleofkeycommoditiesarehard
diskdrives,systemboards,microprocessors,LiquidCrystalDisplays(LCDs),andmemory.

•Remember,allCTOandCMVproductsareloadedinPEWunderthe4-digitMTand3-digitmodel,where
model=“CTO”(Example:1829-CTO).GAVsareloadedinPEWunderthe4-digitMTand3-digitmodel,
wheremodel=a“xedpartnumber”,not“CTO”(Example:1829-F1U).

•PEWcanbeaccessedatthefollowingWebsite:
http://www.lenovo.com/support/site.wss/document.do?lndocid=LOOK-WARNTY
SelectWarrantylookup.InputtheMTandtheSerialnumberandthelistofkeycommoditieswillbe
returnedinthePEWrecordunderCOMPONENTINFORMA TION.

UsingeSupport

ForKeyCommodities(Examples-harddiskdrive,systemboard,microprocessor,LCD,andmemory)

Chapter2.Importantserviceinformation25

•eSupportcanbeusedtoviewthelistofkeycommoditiesbuiltinaparticularmachineserial(thisisthe
samerecordfoundinPEW).

•eSupportcanbeaccessedatthefollowingWebsite:
http://www.lenovo.com/support

•T oviewthekeycommodities,dothefollowing:

1.ClickProducts&ServiceWarranty.

2.ClickCheckWarrantyStatus.

3.OntheWarrantyStatusLookuppage,clickPartsLookup.

4.Typeyourmachinetypeandserialnumber,andthenclickSubmit.Thekeycommoditieswillbe
displayed.

FortheRemainingFRUs(thecompletelistofFRUsattheMTModellevel)

•eSupportcanbeusedtoviewthecompletelistofFRUsforamachinetypeandmodel.

•T oviewthecompletelistofFRUs,dothefollowing:

1.ClickProduct&PartsDetailandthenfollowtheinstructionsonthescreentoreachtheProduct
andPartsDetailspage.

2.ClickthePartsDetailtabtoviewthelistofserviceparts.

UsingtheHMM

ForKeyCommodities(Examples-harddiskdrive,systemboard,microprocessor,LCD,andmemory)

UsetheHMMasaback-uptoPEWandeSupporttoviewthecompletelistofFRUsattheMTModellevel.

26ThinkPadT420andT420iHardwareMaintenanceManual

Chapter3.Generalcheckout

Thischapterpresentsthefollowinginformation:

•“Whattodorst”onpage28

•“Checkoutguide”onpage29
–“SystemsupportingtheLenovoThinkVantageToolboxprogramandthePC-DoctorforDOS

diagnosticsprogram”onpage29

–“SystemsupportingtheLenovodiagnosticsprograms”onpage33

•“Powersystemcheckout”onpage37

Beforeyougotothecheckoutguide,besuretoreadthefollowingimportantnotes.

Importantnotes:

•Onlycertiedtrainedpersonnelshouldservicethecomputer.

•BeforereplacinganyFRU,readtheentirepageonremovingandreplacingFRUs.

•WhenyoureplaceFRUs,itisrecommendedtousenewnylon-coatedscrews.

•Beextremelycarefulduringsuchwriteoperationsascopying,saving,orformatting.Drivesinthecomputer
thatyouareservicingsequencemighthavebeenaltered.Ifyouselectanincorrectdrive,dataorprograms
mightbeoverwritten.

•ReplaceaFRUonlywithanotherFRUofthecorrectmodel.WhenyoureplaceaFRU,makesurethatthemodel
ofthemachineandtheFRUpartnumberarecorrectbyreferringtotheFRUpartslist.

•AFRUshouldnotbereplacedbecauseofasingle,unreproduciblefailure.Singlefailurescanoccurfora
varietyofreasonsthathavenothingtodowithahardwaredefect,suchascosmicradiation,electrostaticdischarge,
orsoftwareerrors.ConsiderreplacingaFRUonlywhenaproblemrecurs.IfyoususpectthataFRUisdefective,
cleartheerrorlogandrunthetestagain.Iftheerrordoesnotrecur,donotreplacetheFRU.

•BecarefulnottoreplaceanondefectiveFRU.

©CopyrightLenovo2012

27

Whattodorst

WhenyoudoreturnaFRU,youmustincludethefollowinginformationinthepartsexchangeformor
partsreturnformthatyouattachtoit:

1.Nameandphonenumberofservicetechnician

2.Dateofservice

3.Dateonwhichthemachinefailed

4.Dateofpurchase

5.Failuresymptoms,errorcodesappearingonthedisplay,andbeepsymptoms

6.ProcedureindexandpagenumberinwhichthefailingFRUwasdetected

7.FailingFRUnameandpartnumber

8.Machinetype,modelnumber,andserialnumber

9.Customer'snameandaddress

Note:Duringthewarrantyperiod,thecustomermayberesponsibleforrepaircostsifthecomputerdamage
wascausedbymisuse,accident,modication,unsuitablephysicaloroperatingenvironment,orimproper
maintenancebythecustomer.Followingisalistofsomecommonitemsthatarenotcoveredunderwarranty
andsomesymptomsthatmightindicatethatthesystemwassubjectedtostressbeyondnormaluse.

Beforecheckingproblemswiththecomputer,determinewhetherthedamageiscoveredunderthewarranty
byreferringtothefollowinglist:

Thefollowingarenotcoveredunderwarranty:

•LCDpanelcrackedfromtheapplicationofexcessiveforceorfrombeingdropped

•Scratched(cosmetic)parts

•Distortion,deformation,ordiscolorationofthecosmeticparts

•Plasticparts,latches,pins,orconnectorsthathavebeencrackedorbrokenbyexcessiveforce

•Damagecausedbyliquidspilledintothesystem

•DamagecausedbytheimproperinsertionofaPCCardortheinstallationofanincompatiblecard

•Improperdiscinsertionoruseofanopticaldrive

•Diskettedrivedamagecausedbypressureonthediskettedrivecover,foreignmaterialinthedrive,
ortheinsertionofadiskettewithmultiplelabels

•Damagedorbentdisketteejectbutton

•Fusesblownbyattachmentofanonsupporteddevice

•Forgottencomputerpassword(makingthecomputerunusable)

•Stickykeyscausedbyspillingaliquidontothekeyboard

•Useofanincorrectacpoweradapteronlaptopproducts

Thefollowingsymptomsmightindicatedamagecausedbynonwarrantedactivities:

•Missingpartsmightbeasymptomofunauthorizedserviceormodication.

•Ifthespindleofaharddiskdrivebecomesnoisy,itmayhavebeensubjectedtoexcessiveforce,
ordropped.

28ThinkPadT420andT420iHardwareMaintenanceManual

Checkoutguide

UsethefollowingproceduresasaguideinidentifyingandcorrectingproblemswiththeThinkPadNotebook.

Note:ThediagnostictestsareintendedtotestonlyThinkPadproducts.Theuseofnon- ThinkPadproducts,
prototypecards,ormodiedoptionscanleadtofalseindicationsoferrorsandinvalidsystemresponses.

1.Identifythefailingsymptomsinasmuchdetailaspossible.

2.Verifythesymptoms.T rytore-createthefailurebyrunningthediagnostictestorbyrepeatingthe
operation.

SystemsupportingtheLenovoThinkVantageToolboxprogramandthe PC-DoctorforDOSdiagnosticsprogram

ThesectionprovidesinformationaboutThinkPadcomputersthatsupporttheLenovoThinkVantageToolbox
programandthePC-Doctor
particularcomputer.

®

forDOSdiagnosticsprogram.Somedescriptionsmightnotapplytoyour

DiagnosticsusingPC-DoctorforDOS

TheThinkPadnotebookcomputerhasatestprogramcalledPC-DoctorforDOS(hereaftercalledPC-Doctor.)
YoucandetecterrorsbyrunningthediagnosticstestincludedinPC-Doctor.

Note:PC-DoctorforDOSisavailableatthefollowingWebsite:
http://www.lenovo.com/support

TocreatethePC-DoctordiagnosticCD,followtheinstructionsontheWebsite.

Forsomepossiblecongurationsofthecomputer,PC-Doctormightnotruncorrectly.Toavoidthisproblem,
youneedtoinitializethecomputersetupbyuseoftheThinkPadSetupprogrambeforeyourunPC-Doctor.

ToentertheThinkPadSetupprogram,doasfollows:

1.Turnonthecomputer.

2.WhentheThinkPadlogocomesup,immediatelypressF1toentertheThinkPadSetupprogram.

Note:Ifasupervisorpasswordhasbeensetbythecustomer,theThinkPadSetupprogrammenuappears
afterthepasswordisentered.Y oucanstarttheThinkPadSetupprogrambypressingEnterinsteadof
enteringthesupervisorpassword;however,youcannotchangetheparametersthatareprotectedbythe
supervisorpassword.

OntheThinkPadSetupprogramscreen,pressF9,Enter,F10,andthenEnter.

Note:Whenyouinitializethecomputerconguration,somedevicesaredisabled,suchastheserialport.If
youtestoneofthesedevices,youwillneedtoenableitbyusingCongurationutilityforDOS.Theutilityis
availableonthefollowingWebsite:
http://www.lenovo.com/support

PC-Doctorcannotbeusedtotestadevicethatisinthedockingstation,evenifthecomputersupportsthe
dockingstation.TotestaUSBdevice,connectittotheUSBconnectorofthecomputer.

Testingthecomputer
Note:ThePC-DoctorforDOSCD-R/CD-RWdiscsupportsonlytestofinternalopticaldiscdrives(CD-RW,

CD-RW/DVDCombo,andDVDMultidrives)onThinkPadcomputers.Itdoesnotsupporttestofanyoptical
discdrivesconnectedthroughUSBdevices,PCcards,CardBuscards,orsimilar.TheUSBlimitationonly
appliestotestingofthedevice.UsingabootablePC-DoctorforDOSCD/DVD,thesystemcanbestarted
fromaUSBattachedopticaldrive.

Chapter3.Generalcheckout29

Torunthetest,doasfollows:

Diagnostics

Run Normal Test
Run Quick Test
CPU/Coprocessor

Systemboard

System Memory

Video Adapter
Fixed Disks
Diskette Drives
Other Devices
Communication

Interactive Tests Hardware Info Utility Quit F1=Help

PC-DOCTOR 2.0 Copyright 2008 PC-Doctor, Inc. All Rights Reserved.

Use the cursor keys and ESC to move in menus. Press ENTER to select.

Wireless LAN

1.Turnoffthecomputer.

2.Makesurethattheopticaldrivethatissupportedasastartupdeviceisinstalledtothecomputer.

3.Turnonthecomputer.Ifthecomputercannotbepoweredon,goto“Powersystemcheckout”on
page37,andcheckthepowersources.

Ifanerrorcodeappears,goto“Symptom-to-FRUindex”onpage47.

4.WhentheThinkPadlogocomesup,immediatelypressF12toentertheBootMenu.

5.InsertthePC-DoctorCDintotheopticaldrive.

6.PresscursorkeystoselectATAPICDx(x:0,1,...)andthenpressEnter.

7.Followtheinstructionsonthescreen.

8.ThemainpanelofPC-Doctorappears.

9.SelectDiagnosticswiththearrowkeys,andpressEnter.

Note:Y oucanselectanitemnotonlywiththearrowkeys,butalsowiththeTrackPoint
InsteadofpressingEnter,clicktheleftbutton.

Apull-downmenuappears.(Itsexactformdependsonthemodel.)

Note:PC-Doctormenudoesnotmeantheformalsupportdevicelist.Someunsupporteddevicenames
mayappearinthePC-Doctormenu.

Theoptionsonthetestmenuareasfollows:

DiagnosticsInteractiveTests

•RunNormalT est

•RunQuickT est

•CPU/Coprocessor

•SystemMemory

•Systemboard

•VideoAdapter

•FixedDisks

•DisketteDrives

•OtherDevices

•Communication

•WirelessLAN

Notes:

•IntheKeyboardtestinInteractiveTests,theFnkeyshouldbehelddownforatleast2seconds;otherwise,it
cannotbesensed.

•Keyboard

•Video

•InternalSpeaker

•Mouse

•Diskette

•SystemLoad

•OpticalDriveT est

•IntelWLANRadioTest

®

pointer.

30ThinkPadT420andT420iHardwareMaintenanceManual

DiagnosticsInteractiveTests

•VideoAdaptertestsupportsonlytheLCDdisplayontheThinkPadNotebook.Ifyouhaveanexternalmonitor

attachedtoyourcomputer,detachitbeforerunningPC-DoctorforDOS.

•T otestDigitalSignatureChip,thesecuritychipmustbesettoActive.

10.Runtheapplicablefunctiontest.

11.Followtheinstructionsonthescreen.Ifthereisaproblem,PC-Doctorshowsmessagesdescribingit.

12.Toexitthetest,selectQuit—ExitDiag.T ocancelthetest,pressEsc.

Note:AfterrunningPC-Doctor,checkthetimeanddateonthesystemandresetthemiftheyareincorrect.

DetectingsysteminformationwithPC-Doctor

PC-Doctorcandetectthefollowingsysteminformation:

HardwareInfo

•SystemConguration

•MemoryContents

•PhysicalDiskDrives

•VGAInformation

•A T ADriveInfo

•PCIInformation

•PNPISAInfo

•SMBIOSInfo

•VESALCDInfo

•HardwareEventsLog

Utility

•RunExternalT ests

•BenchmarkSystem

•DOSShell

•T echSupportForm

•BatteryRundown

•EraseDriveContents

•ViewPCDRHostLog

LenovoThinkVantageT oolbox

LenovoThinkVantage
Itenablesyoutoviewsymptomsofcomputerproblemsandsolutionsforthem,andincludesautomatic
noticationwhenactionisrequired,computingassistance,advanceddiagnostics,anddiagnostichistory.

Notes:

•ThelatestLenovoThinkVantageToolboxisavailableatthefollowingWebsite:
http://web.lenovothinkvantagetoolbox.com/

•T oinstallthelatestLenovoThinkVantageToolboxonthecomputer ,clickDownloadLenovoThinkVantage
Toolbox,andthenfollowtheinstructionsontheWebsite.

Torunthisprogram,doasfollows:

Windows7:

WhiletheWindowsoperatingsystemisrunning,presstheThinkVantagebutton.

Tostartthisprogram,dothefollowing:

•ClickStart➙ControlPanel➙SystemandSecurity➙Lenovo–SystemHealthandDiagnostics.

®

ToolboxisadiagnosticprogramthatworksthroughtheWindowsoperatingsystem.

Chapter3.Generalcheckout31

WindowsVista

®

andWindowsXP:

ClickStart➙AllPrograms➙ThinkVantage➙LenovoThinkVantageT oolbox

Followtheinstructionsonthescreen.LenovoThinkVantageT oolboxalsohasproblemdeterminationaids
thatdeterminesoftwareandusageproblems.

Foradditionalinformationaboutthisprogram,seetheHelpfortheprogram.

32ThinkPadT420andT420iHardwareMaintenanceManual

FRUtests

ThefollowingtableshowsthetestforeachFRU.

Table1.FRUtests

FRUApplicabletest

Systemboard1.Diagnostics➙CPU/Coprocessor

2.Diagnostics➙Systemboard

3.IfthedockingstationortheportreplicatorisattachedtotheThinkPadNotebook,
detachit.

4.Placethecomputeronahorizontalsurface,andrunDiagnostics➙ThinkPad

Devices➙HDDActiveProtectionT est.

Note:Donotapplyanyphysicalshocktothecomputerwhilethetestisrunning.

Power

LCDunit

Audio

SpeakerInteractiveT ests➙InternalSpeaker

Keyboard

Harddiskdriveorsolidstate
drive

Diskettedrive1.Diagnostics➙DisketteDrives

Opticaldrive1.Diagnostics➙OtherDevices➙OpticalDrive

Memory

TrackPointorpointing
device

Diagnostics➙ThinkPadDevices➙acpoweradapter ,Battery1(Battery2)

1.Diagnostics➙VideoAdapter

2.InteractiveT ests➙Video

EntertheThinkPadSetupprogramandchangeSerialATA(SATA)settingto

Compatibility,andrunDiagnostics➙OtherDevice➙ConexantAudio.

Note:OnceAudiotestisdone,thenosoundisheardthistest.Inthiscase,turnoff

andturnonthecomputer.Then,runthistestagain.

1.Diagnostics➙Systemboard➙Keyboard

2.InteractiveT ests➙Keyboard

EntertheThinkPadSetupprogramandchangeSerialATA(SATA)settingto
Compatibility,andrunDiagnostics➙FixedDisks.

2.InteractiveT ests➙Diskette

2.InteractiveTests➙OpticalDriveT est

1.IftwoDIMMsareinstalled,removeoneofthemandrunDiagnostics➙System
Memory.

2.Iftheproblemdoesnotrecur,returntheDIMMtoitsplace,removetheotherone,
andrunthetestagain.

IftheT rackPointdoesnotwork,checkthecongurationasspeciedintheThinkPad
Setupprogram.IftheT rackPointisdisabled,selectAutomatictoenableit.

AfteryouusetheT rackPoint,thepointermaydriftonthescreenforashorttime.This
driftcanoccurwhenaslight,steadypressureisappliedtotheT rackPointpointer.
Thissymptomisnotahardwareproblem.Ifthepointerstopsafterashorttime,no
serviceactionisnecessary.

IfenablingtheT rackPointdoesnotcorrecttheproblem,continuewiththefollowing:

•InteractiveTests➙Mouse

TouchPad

IftheT ouchPaddoesnotwork,checkthecongurationasspeciedintheThinkPad
Setupprogram.IftheTouchPadisdisabled,selectAutomatictoenableit.Ifenabling
theT ouchPaddoesnotcorrecttheproblem,continuewiththefollowing:

•InteractiveTests➙Mouse

SystemsupportingtheLenovodiagnosticsprograms

ThesectionprovidesinformationaboutThinkPadcomputersthatsupporttheLenovodiagnosticsprograms.
Somedescriptionsmightnotapplytoyourparticularcomputer.

Chapter3.Generalcheckout33

TheLenovodiagnosticsprogramsincludefollowing:

•LenovoSolutionCenter

•Quicktestprograms

•UEFIdiagnosticprogram

•Bootablediagnosticprograms

LenovoSolutionCenter

TheLenovoSolutionCenterprogramenablesyoutotroubleshootandresolvecomputerproblems.It
combinesdiagnostictests,systeminformationcollection,securitystatus,andsupportinformation,along
withhintsandtipsformaximumsystemperformance.

Note:TheLenovoSolutionCenterprogramisavailableonlyonmodelspreinstalledwiththeWindows7
operatingsystem.Italsocanbedownloadedfromhttp://www.lenovo.com/diags.

ToruntheLenovoSolutionCenterprogram,clickStart➙ControlPanel➙SystemandSecurity➙Lenovo

-SystemHealthandDiagnostics,andthenfollowtheinstructionsonthescreen.

Foradditionalinformationaboutthisprogram,seethehelpinformationsystem.

Quicktestprograms

LenovoHardDriveQuickT estandLenovoMemoryQuickTestaretwoquicktestprogramsthatenableyou
totroubleshootandresolvecomputerinternalstorageandmemoryproblems.

Notes:

•IfthecomputeryouareservicingisnotinstalledwiththeLenovoSolutionCenterprogram,youcan
downloadthequicktestprogramsfromtheLenovoSupportWebsite.

•ThetwoprogramsareapplicabletocomputersinstalledwiththeWindows7,WindowsXP ,Windows
Server2003,orWindowsServer2008operatingsystem.

Todownloadandinstallaquicktestprogram,gotohttp://www.lenovo.com/diags,andfollowtheinstructions
ontheWebsite.

Torunaquicktestusingthedownloadedprogram,dothefollowing:

1.GototheC:\SWTOOLS\ldiagfolder.

2.Double-clickthegui_lsc_lite.exele.

3.WhentheUserAccountControlwindowopens,clickYes.

4.Selectthedeviceclasstobetested.

5.Selectthedevicestobetested.

6.Selecttheteststobeperformed.

7.Followtheinstructionsonthescreentostartthetest.Whenaproblemisdetected,information
messageswillbedisplayed.Refertothemessagestotroubleshoottheproblem.

UEFIdiagnosticprogram

AUEFIdiagnosticprogramispreinstalledonthecomputer.Itenablesyoutotestmemoryandinternal
storageproblems,viewsysteminformation,andcheckandrecoverbadsectorsoninternalstoragedevices.

ToruntheUEFIdiagnosticprogram,dothefollowing:

34ThinkPadT420andT420iHardwareMaintenanceManual

1.Turnonthecomputer.Ifthecomputercannotbeturnedon,goto“Powersystemcheckout”onpage37,
andcheckthepowersources.Ifanerrorcodeisdisplayed,goto“Symptom-to-FRUindex”onpage47
forerrorcodedescriptionsandtroubleshootinghints.

2.WhentheThinkPadlogoisdisplayed,repeatedlypressandreleasetheF12key.WhentheBootMenu
windowopens,releasetheF12key.

3.PresstheTabkeytoswitchtotheApplicationMenuwindow.

4.UsethearrowkeystoselectLenovoDiagnosticsandthenpressEnter.ThemainscreenoftheUEFI
diagnosticprogramisdisplayed.

5.Followtheinstructionsonthescreentousethediagnosticprogram.

Theoptionsonthemainscreenareasfollows:

TestsTools

•QuickMemoryT est

•QuickStorageDeviceT est

•ExitApplication

•SystemInformation

•RecoverBadSectorsTool

Bootablediagnosticprograms

IfthecomputeryouareservicingisnotinstalledwiththeUEFIdiagnosticprogram,youcandownloada
bootablediagnosticprogramfromtheLenovoSupportWebsite.Thebootablediagnosticprogramsenable
youtotestcomputermemoryandinternalstoragedevices,viewsysteminformation,andcheckandrecover
theinternalstoragedevices.Tousethebootablediagnosticprograms,youcancreateabootablediagnostic
mediumonaUSBdeviceorCD.

Tocreateabootablediagnosticmedium,dothefollowing:

1.Gotohttp://www.lenovo.com/diags.

2.ClickLenovoBootableDiagnostics.

3.FollowtheinstructionsontheWebsitetocreateabootablediagnosticmediumonaUSBdeviceorCD.

Tousethediagnosticmediumyouhavecreated,dooneofthefollowing:

•IfyouhavecreatedthebootablediagnosticmediumonaUSBdevice,dothefollowing:

1.AttachtheUSBdevicetothecomputer.

2.Turnonthecomputer.Ifthecomputercannotbeturnedon,goto“Powersystemcheckout”onpage
,andcheckthepowersources.Ifanerrorcodeisdisplayed,goto“Symptom-to-FRUindex”on

37
page47forerrorcodedescriptionsandtroubleshootinghints.

3.WhentheThinkPadlogoisdisplayed,repeatedlypressandreleasetheF12key.WhentheBoot

Menuwindowopens,releasetheF12key.

4.UsethearrowkeystoselectUSBHDDandthenpressEnter.Thediagnosticprogramwillbe

launchedautomatically.

5.Followtheinstructionsonthescreentousethediagnosticprogram.

•IfyouhavecreatedthebootablediagnosticmediumonaCD,dothefollowing:

1.Turnonthecomputer.Ifthecomputercannotbeturnedon,goto“Powersystemcheckout”onpage

37,andcheckthepowersources.Ifanerrorcodeisdisplayed,goto“Symptom-to-FRUindex”on
page47forerrorcodedescriptionsandtroubleshootinghints.

2.InserttheCDintotheopticaldrive.

3.Restartthecomputer.

4.WhentheThinkPadlogoisdisplayed,repeatedlypressandreleasetheF12key.WhentheBoot

Menuwindowopens,releasetheF12key.

Chapter3.Generalcheckout35

5.UsethearrowkeystoselectATAPICDx(x:0,1,...)andthenpressEnter.Thediagnosticprogram
willbelaunchedautomatically.

6.Followtheinstructionsonthescreentousethediagnosticprogram.

36ThinkPadT420andT420iHardwareMaintenanceManual

Powersystemcheckout

1

2

3

(20V)

Toverifyasymptom,dothefollowing:

1.Turnoffthecomputer.

2.Removethebatterypack.

3.Connecttheacpoweradapter.

4.Checkthatpowerissuppliedwhenyouturnonthecomputer.

5.Turnoffthecomputer.

6.Disconnecttheacpoweradapterandinstallthechargedbatterypack.

7.Checkthatthebatterypacksuppliespowerwhenyouturnonthecomputer.

Ifyoususpectapowerproblem,seetheappropriateoneofthefollowingpowersupplycheckouts:

•“Checkingtheacpoweradapter”onpage37

•“Checkingoperationalcharging”onpage37

•“Checkingthebatterypack”onpage38

•“Checkingthebackupbattery”onpage38

Checkingtheacpoweradapter

Youareherebecausethecomputerfailsonlywhentheacpoweradapterisused.

•Ifthepowerproblemoccursonlywhenthedockingstationortheportreplicatorisused,replacethe
dockingstationortheportreplicator.

•Ifthepower-onindicatordoesnotturnon,checkthepowercordoftheacpoweradapterforcorrect
continuityandinstallation.

•Ifthecomputerdoesnotchargeduringoperation,goto“Checkingoperationalcharging”onpage37

.

Tochecktheacpoweradapter,dothefollowing:

1.Unplugtheacpoweradaptercablefromthecomputer.

2.Measuretheoutputvoltageattheplugoftheacpoweradaptercable.Seethefollowinggure:

Pin

1+20

20

3

Note:Outputvoltageofpinno.2oftheacpoweradaptermaydifferentfromtheoneyouareservicing.

3.Ifthevoltageisnotcorrect,replacetheacpoweradapter.

4.Ifthevoltageisacceptable,dothefollowing:

•Replacethesystemboard.

•IftheproblempersistsandyoursystemsupportsthePCdoctorforDOS,goto“FRUtests”on
page33.

Note:Noisefromtheacpoweradapterdoesnotalwaysindicateadefect.

Voltage(Vdc)

Ground

Checkingoperationalcharging

Tocheckwhetherthebatterychargesproperlyduringoperation,useadischargedbatterypackorabattery
packthathaslessthan50%ofthetotalpowerremainingwheninstalledinthecomputer.

Chapter3.Generalcheckout37

Performoperationalcharging.Ifthebatterystatusindicatororicondoesnotturnon,removethebattery

1(+)

2(+)

3

4

5

6(-)

7(-)

packandletitreturntoroomtemperature.Reinstallthebatterypack.Ifthechargeindicatororiconstilldoes
notturnon,replacethebatterypack.

Ifthechargeindicatorstilldoesnotturnon,replacethesystemboard.Thenreinstallthebatterypack.Ifitis
stillnotcharged,gotothenextsection.

Checkingthebatterypack

BatterychargingdoesnotstartuntilthePowerManagerBatteryGaugeshowsthatlessthan96%ofthe
totalpowerremains;underthisconditionthebatterypackcanchargeto100%ofitscapacity.Thisprotects
thebatterypackfrombeingoverchargedorfromhavingashortenedlife.

Tocheckyourbattery,moveyourcursortothePowerManagerBatteryGaugeiconintheicontrayofthe
Windowstaskbarandwaitforamoment(butdonotclick),andthepercentageofbatterypowerremaining
isdisplayed.Togetdetailedinformationaboutthebattery,double-clickthePowerManagerBattery
Gaugeicon.

Note:Ifthebatterypackbecomeshot,itmaynotbeabletocharge.Removeitfromthecomputerandleave
itatroomtemperatureforawhile.Afteritcoolsdown,reinstallandrechargeit.

Tocheckthebatterypack,dothefollowing:

1.Poweroffthecomputer.

2.Removethebatterypackandmeasurethevoltagebetweenbatteryterminals1(+)and7(-).Seethe
followinggure:

Terminal

1+0to+16.8

7

Voltage(Vdc)

Ground(-)

3.Ifthevoltageislessthan+11.0Vdc,thebatterypackhasbeendischarged.

Note:Rechargingwilltakeatleast3hours,eveniftheindicatordoesnotturnon.

Ifthevoltageisstilllessthan+11.0Vdcafterrecharging,replacethebattery.

4.Ifthevoltageismorethan+11.0Vdc,measuretheresistancebetweenbatteryterminals5and7.
Theresistancemustbe4to30KΩ.Iftheresistanceisnotcorrect,replacethebatterypack.Ifthe
resistanceiscorrect,replacethesystemboard.

Checkingthebackupbattery

Dothefollowing:

1.Poweroffthecomputer,andunplugtheacpoweradapterfromit.

2.Turnthecomputerupsidedown.

3.Removethebatterypack(see“1010Batterypack”onpage67).

4.Removethebackupbattery(see“1100Backupbattery”onpage83).

5.Measurethevoltageofthebackupbattery.Seethefollowinggure.

38ThinkPadT420andT420iHardwareMaintenanceManual

Wire

Red+2.5to+3.2

Black

Voltage(Vdc)

Ground

•Ifthevoltageiscorrect,replacethesystemboard.

•Ifthevoltageisnotcorrect,replacethebackupbattery.

•Ifthebackupbatterydischargesquicklyafterreplacement,replacethesystemboard.

Chapter3.Generalcheckout39

40ThinkPadT420andT420iHardwareMaintenanceManual

Chapter4.Relatedserviceinformation

Thischapterpresentsfollowinginformation:

•“RestoringthefactorycontentsbyusingRecoveryDiscSet”onpage41

•“Passwords”onpage42

•“Powermanagement”onpage45

•“Symptom-to-FRUindex”onpage47

ServiceWebsite:

Whenthelatestmaintenancedisketteandthesystemprogramservicediskettebecomeavailable,theywillbeposted
on
http://www.lenovo.com/support

RestoringthefactorycontentsbyusingRecoveryDiscSet

Whentheharddiskdrive(HDD)orsolidstatedrive(SSD)isreplacedbecauseofafailure,noproductrecovery
programisonthenewdrive.Inthiscase,youmustusetheRecoveryDiscSetforthecomputer.Orderthe
RecoveryDiscSetandthedriveatthesametimesothatyoucanrecoverthenewdrivewiththepre-installed
softwarewhentheyarrive.Forinformationonwhichdiscstoorder,see“Recoverydiscs”onpage166

TherecoverydiscsetconsistsoftheuserinstructionsandthefollowingsetofDVDstorestorethecomputer
totheoriginalfactoryconguration.

.

OperatingSystemRecoveryDisc(onedisc)

ThisdiscrestorestheMicrosoft

®

Windowsoperating

system.Usethisdisctostarttherecoveryprocess.

ApplicationsandDriversRecoveryDisc(oneor
morediscs)

SupplementalRecoveryDisc

Thisdiscrestoresthepreinstalledapplicationsand
driversonthecomputer.

Thisdisccontainsadditionalcontent,suchas
updatestothesoftwarethatwaspreinstalledonthe
computer.Notallrecoverydiscsetscomewitha
SupplementalRecoveryDisc.

Notes:

•Y oumusthaveaDVDdrivetousetherecoverydiscs.IfyoudonothaveaninternalDVDdrive,you
canuseanexternalUSBDVDdrive.

•Duringtherecoveryprocess,alldataonthedrivewillbedeleted.Ifpossible,copyanyimportantdata
orpersonallesthatyouwanttokeepontoremovablemediaoranetworkdrivebeforeyoustartthe
recoveryprocess.

Torestorethecomputertotheoriginalfactorycongurationusingtherecoverydiscset,dothefollowing:

Note:Recoverycantakeonetotwohourstocomplete.Thelengthoftimedependsonthemethodyouuse.Ifyou
userecoverydiscs,therecoveryprocesswilltakeabouttwohours.

1.MaketheCD/DVDdrivetherststartupdeviceinthestartupsequenceusingthefollowingprocedure:

a.PressandholddowntheF1key,andthenturnonthecomputer.Whenthelogoscreenisdisplayed

orifyouhearrepeatingbeeps,releasetheF1key.TheThinkPadSetupprogramopens.

b.UsethearrowkeystoselectStartup➙Boot.

c.SelecttheCD/DVDdriveasthe1stBootDevice.

©CopyrightLenovo2012

41

2.InserttheOperatingSystemRecoveryDiscintotheDVDdrive.

3.PressF10tosavetheThinkPadSetupprogramcongurationchanges.Followtheinstructionsonthe
screentobegintherecoveryprocess.

4.SelectyourlanguageandclickNext.

5.Readthelicense.Ifyouagreewiththetermsandconditions,selectIacceptthesetermsand
conditionsandthenclickNext.Ifyoudonotagreewiththetermsandconditions,followthe
instructionsonthescreen.

6.ClickYesinthedisplayedwindowtobegintheoperatingsystemrecoveryprocess.

7.InserttheApplicationsandDriversRecoveryDiscwhenpromptedandthenclickOKtobeginthe
applicationsanddriversrecoveryprocess.

8.IfyouhaveaSupplementalRecoveryDisc,insertitwhenpromptedandclickYes.Ifyoudonothavea
SupplementalRecoveryDisc,clickNo.

9.Whenallofthedatahasbeencopiedfromthelastdiscinthesetandhasbeenprocessed,removethe
discandrestartthecomputer.

Note:Therestoftherecoveryprocessisfullyautomatedandnoactionisrequiredbyyou.The
computerwillrestartintotheMicrosoftWindowsdesktopseveraltimesandyoumightexperience
periodswhennoactivityisapparentonthescreenforseveralminutesatatime.Thisisnormal.

10.Whentherecoveryprocessiscomplete,theSetUpWindowsscreenisdisplayed.Followthe
instructionsonthescreentocompletetheWindowssetup.

11.AfteryouhavecompletedtheWindowssetup,youmightwanttorestoretheoriginalstartupsequence.
StarttheThinkPadSetupprogramandthenpressF9torestorethedefaultsettings.PressF10tosave
andexittheThinkPadSetupprogram.

Note:Afterrestoringadrivetothefactorydefaultsettings,youmightneedtoreinstallsomedevicedrivers.

Passwords

AsmanyasthreepasswordsmaybeneededforanyThinkPadNotebook:thepower-onpassword(POP),
thehard-diskpassword(HDP),andthesupervisorpassword(SVP).

Ifanyofthesepasswordshasbeenset,apromptforitappearsonthescreenwheneverthecomputeris
turnedon.Thecomputerdoesnotstartuntilthepasswordisentered.

Note:IfonlyanSVPisinstalled,thepasswordpromptdoesnotappearwhentheoperatingsystemisbooted.

Power-onpassword

Apower-onpassword(POP)protectsthesystemfrombeingpoweredonbyanunauthorizedperson.The
passwordmustbeenteredbeforeanoperatingsystemcanbebooted.ForhowtoremovethePOP,see
“Howtoremovethepower-onpassword”onpage43

.

Hard-diskpassword

Therearetwohard-diskpasswords(HDPs):

•UserHDP—fortheuser

•MasterHDP—forthesystemadministrator,whocanuseittogetaccesstotheharddiskeveniftheuser
haschangedtheuserHDP

Note:TherearetwomodesfortheHDP:UseronlyandMaster+User.TheMaster+Usermoderequires
twoHDPs;thesystemadministratorentersbothinthesameoperation.Thesystemadministratorthen
providestheuserHDPtothesystemuser.

42ThinkPadT420andT420iHardwareMaintenanceManual

Attention:IftheuserHDPhasbeenforgotten,checkwhetheramasterHDPhasbeenset.Ifithas,itcanbe

usedforaccesstotheharddiskdrive.IfnomasterHDPisavailable,neitherLenovonorLenovoauthorized
servicetechniciansprovideanyservicestoreseteithertheuserorthemasterHDP ,ortorecoverdatafrom
theharddiskdrive.Theharddiskdrivecanbereplacedforascheduledfee.

ForhowtoremovethePOP ,see“Howtoremovethehard-diskpassword”onpage43.

Supervisorpassword

Asupervisorpassword(SVP)protectsthesysteminformationstoredintheThinkPadSetupprogram.
TheusermustentertheSVPinordertogetaccesstotheThinkPadSetupprogramandchangethe
systemconguration.

Attention:IftheSVPhasbeenforgottenandcannotbemadeavailabletotheservicetechnician,thereisno
serviceproceduretoresetthepassword.Thesystemboardmustbereplacedforascheduledfee.

Howtoremovethepower-onpassword

ToremoveaPOPthatyouhaveforgotten,dothefollowing:

(A)IfnoSVPhasbeenset:

1.Turnoffthecomputer.

2.Removethebatterypack.Forhowtoremovethebatterypack,see“1010Batterypack”onpage67.

3.Removethebackupbattery.Forhowtoremovethebackupbattery,see“1100Backupbattery”on
page83.

4.TurnonthecomputerandwaituntilthePOSTends.AfterthePOSTends,thepasswordpromptdoes
notappear.ThePOPhasbeenremoved.

5.Reinstallthebackupbatteryandthebatterypack.

(B)IfanSVPhasbeensetandisknownbytheservicetechnician:

1.Turnonthecomputer.

2.WhentheThinkPadlogocomesup,immediatelypressF1toentertheThinkPadSetupprogram.When
thePOPiconisappearingonthescreen,enterthePOP .

3.SelectSecurity,usingthecursordirectionalkeystomovethemenu.

4.SelectPassword.

5.SelectPower-OnPassword.

6.TypethecurrentSVPintheEnterCurrentPasswordeld.thenleavetheEnterNewPasswordeld
blank,andpressEntertwice.

7.IntheChangeshavebeensavedwindow,pressEnter.

8.PressF10;then,intheSetupconrmationwindow,selectYes.

Howtoremovethehard-diskpassword

Attention:IfUseronlymodeisselectedandtheuserHDPhasbeenforgottenandcannotbemade

availabletotheservicetechnician,neitherLenovonorLenovoauthorizedservicetechniciansprovideany
servicestoresettheuserHDPsortorecoverdatafromtheharddiskdrive.Theharddiskdrivecanbe
replacedforascheduledfee.

ToremoveauserHDPthathasbeenforgotten,whentheSVPandthemasterHDPareknown,dothe
following:

1.Turnonthecomputer.

Chapter4.Relatedserviceinformation43

2.WhentheThinkPadlogocomesup,immediatelypressF1toentertheThinkPadSetupprogram.When
thePOPiconisappearingonthescreen,enterthePOP .

3.SelectSecurity,usingthecursordirectionalkeystomovethemenu.

4.SelectPassword.

5.SelectHard-diskxpassword,wherexistheletteroftheharddiskdrive.Apop-upwindowopens.

6.SelectMasterHDP.

7.TypethecurrentmasterHDPintheEnterCurrentPasswordeld.thenleavetheEnterNewPassword
eldblank,andpressEntertwice.

8.PressF10.

9.SelectYesintheSetupCongurationwindow.BothuserHDPandmasterHDPwillhavebeenremoved.

44ThinkPadT420andT420iHardwareMaintenanceManual

Powermanagement

Toreducepowerconsumption,thecomputerhasthreepowermanagementmodes:screenblank,sleep
(standbyinWindowsXP),andhibernation.

Screenblankmode

Ifthetimesetonthe“Turnoffmonitor”timerintheoperatingsystemexpires,theLCDbacklightturnsoff.

Toputthecomputerintoscreenblankmode,doasfollows:

1.PressFn+F3.Apanelforselectingapowerplan(inWindowsXP ,powerscheme)appears.

2.SelectPoweroffdisplay(keepcurrentpowerplan)(inWindowsXP ,keepcurrentpowerscheme).

Toendscreenblankmodeandresumenormaloperation,pressanykey.

Sleep(standby)mode

Whenthecomputerenterssleep(standby)mode,thefollowingeventsoccurinadditiontowhatoccurs
inscreenblankmode:

•TheLCDispoweredoff.

•Theharddiskdriveispoweredoff.

•TheCPUstops.

Toentersleep(standby)mode,pressFn+F4.

Note:Y oucanchangetheactionoftheFn+F4keycombinationbychangingthesettingsinPowerManager.

Incertaincircumstances,thecomputergoesintosleep(standby)modeautomatically:

•Ifa“suspendtime”hasbeensetonthetimer,andtheuserdoesnotdoanyoperationwiththekeyboard,
theTrackPoint,theharddisk,theparallelconnector,orthediskettedrivewithinthattime.

•Ifthebatteryindicatorblinksorange,indicatingthatthebatterypowerislow.

Note:Evenifyoudonotsetthelow-batteryalarm,thechargeindicatornotiesyouwhenthebatteryislow,
andthenthecomputerentersthepower-savingmodeautomatically.

Tocausethecomputertoreturnfromsleep(standby)modeandresumeoperation,dooneofthefollowing:

•PresstheFnkey.

•OpentheLCDcover.

•T urnonthepowerswitch.

Also,ineitherofthefollowingevents,thecomputerautomaticallyreturnsfromsleep(standby)modeand
resumesoperation:

•Theringindicator(RI)issignaledbyaserialdeviceoraPCCarddevice.

•Thetimesetontheresumetimerelapses.

Note:Thecomputerdoesnotacceptanyinputimmediatelyafteritenterssleep(standby)mode.Waita
fewsecondsbeforetakinganyactiontoreenteroperationmode.

Hibernationmode

Inhibernationmode,thefollowingoccurs:

•Thesystemstatus,RAM,VRAM,andsetupdataarestoredontheharddisk.

Chapter4.Relatedserviceinformation45

•Thesystemispoweredoff.

Note:Ifthecomputerentersthehibernationmodewhileitisdockedtothedockingstation,donotundockit
beforeresumingnormaloperation.Ifyoudoundockitandthentrytoresumenormaloperation,youwillget
anerrormessage,andyouwillhavetorestartthesystem.

Tocausethecomputertoenterhibernationmode,doanyofthefollowing:

•PresstheFn+F12keys.

•Ifyouhavedenedoneofthefollowingactionsastheeventthatcausesthesystemtogointohibernation
mode,performthataction.
–Closingthelid.
–Pressingthepowerbutton.
–PressingFn+F4keys.

Also,thecomputergoesintohibernationmodeautomaticallyineitherofthefollowingconditions:

•Ifa“hibernationtime”hasbeensetonthetimer,andiftheuserdoesnotdoanyoperationwiththe
keyboard,theT rackPoint,theharddiskdrive,theparallelconnector,orthediskettedrivewithinthattime.

•Ifthetimerconditionsaresatisedinsuspendmode.

Whenthepoweristurnedon,thecomputerreturnsfromhibernationmodeandresumesoperation.The
hibernationleinthebootrecordontheharddiskdriveisread,andsystemstatusisrestoredfromthe
harddiskdrive.

46ThinkPadT420andT420iHardwareMaintenanceManual

Symptom-to-FRUindex

Thissectioncontainsfollowinginformation:

•“Numericerrorcodes”onpage47

•“Errormessages”onpage49

•“Beepsymptoms”onpage50

•“No-beepsymptoms”onpage50

•“LCD-relatedsymptoms”onpage50

•“Intermittentproblems”onpage52

•“Undeterminedproblems”onpage52

Thesymptom-to-FRUindexinthissectionlistssymptomsanderrorsandtheirpossiblecauses.Themost
likelycauseislistedrst,inboldfacetype.

Note:DotheFRUreplacementorotheractionsinthesequenceshowninthecolumnheaded“FRUor
action,insequence. ”IfreplacingaFRUdoesnotsolvetheproblem,puttheoriginalpartbackinthe
computer.DonotreplaceanondefectiveFRU.

Thisindexcanalsohelpyoudetermine,duringregularservicing,whatFRUsarelikelytoneedtobe
replacednext.

AnumericerrorisdisplayedforeacherrordetectedinPOSTorsystemoperation.Inthedisplays,ncan
beanynumber.

Ifnonumericcodeisdisplayed,checkthenarrativedescriptionsofsymptoms.Ifthesymptomisnot
describedthere,goto“Intermittentproblems”onpage52

.

Note:ForadevicenotsupportedbydiagnosticcodesintheThinkPadNotebooks,seethemanualforthatdevice.

Numericerrorcodes

Table2.Numericerrorcodes

Symptomorerror

0177

BadSVPdata,stopPOSTtask—Thechecksumofthe
supervisorpasswordintheEEPROMisnotcorrect.

0182

BadCRC2.EntertheThinkPadSetupprogramandload
Setupdefaults.—ThechecksumoftheCRS2settingin
theEEPROMisnotcorrect.

0183

BadCRCofSecuritySettingsinEFIVariable.Enterthe
ThinkPadSetupprogram.

0187

EAIAdataaccesserror—TheaccesstoEEPROMisfailed.

0188

InvalidRFIDSerializationInformationArea.

0189

InvalidRFIDcongurationinformationarea—The
EEPROMchecksumisnotcorrect.

0190

Criticallow-batteryerror

FRUoraction,insequence

Systemboard.

1.RuntheThinkPadSetupprogram.PressF9,and
Entertoloadthedefaultsetting.Thensavethe
currentsettingbypressingF10.

2.Systemboard.

Systemboard.

Systemboard.

Systemboard.

1.Chargethebatterypack.

2.Batterypack.

Chapter4.Relatedserviceinformation47

Table2.Numericerrorcodes(continued)

Symptomorerror

0191

SystemSecurity—InvalidRemoteChangerequested.

0199

SystemSecurity—Securitypasswordretrycount
exceeded.

0251

SystemCMOSchecksumbad—Defaultconguration
used.

0271

Real-timeclockerror.Checkdateandtimesettings.

1802

Unauthorizednetworkcardispluggedin—Turnoffand
removetheminiPCInetworkcard.

1820

Morethanoneexternalngerprintreaderisattached.
Poweroffandremoveallbutthereaderthatyousetup
withinyourmainoperatingsystem.

2000

HardDriveActiveProtectionsensordiagnostics
failed.Press<Esc>tocontinue.Press<F1>toenter
SETUP

2100

DetectionerroronHDD0(MainHDD)

2101

DetectionerroronHDD1(UltrabayHDD)

2102

DetectionerroronHDD2(MiniSATA)

2110

ReaderroronHDD0(MainHDD)

2111

ReaderroronHDD1(UltrabayHDD)

2112

ReaderroronHDD2(MiniSA T A)

2200

MachineTypeandSerialNumberareinvalid.

2201

MachineUUIDisinvalid

FRUoraction,insequence

1.RuntheThinkPadSetupprogram,andthensave
currentsettingbypressingF10.

2.Systemboard.

1.RuntheThinkPadSetupprogram,andthensave

thecurrentsettingbypressingF10.

2.Systemboard.

1.Chargethebackupbatteryformorethan8hours

byconnectingtheacpoweradapter.

2.ReplacethebackupbatteryandruntheThinkPad
setupprogramtoresetthetimeanddate.

RuntheThinkPadSetupprogramtoresetthetime
anddate.

1.RemoveMiniPCInetworkcard.

2.Systemboard.

Removeallbutthereaderthatyousetupforthe
authentication.

1.Undockdockingstationorportreplicatorifitis
attachedtotheThinkPadNotebook.

2.PlacetheThinkPadNotebookonahorizontalsurface.
Donotapplyanyphysicalshocktothecomputer.

3.RunDiagnostics➙ThinkPadDevices➙HDD
ActiveProtectionT est.

1.Reseattheharddiskdrive.

2.Mainharddiskdrive.

3.Systemboard.

1.Reseattheharddiskdrive.

2.Ultrabayharddiskdrive.

3.Systemboard.

1.ReseattheMiniSATAdevice.

2.MiniSA T Adevice.

3.Systemboard.

1.Reseattheharddiskdrive.

2.Mainharddiskdrive.

3.Systemboard.

1.Reseattheharddiskdrive.

2.Ultrabayharddiskdrive.

3.Systemboard.

1.ReseattheMiniSATAdevice.

2.MiniSA T Adevice.

3.Systemboard.

Systemboard.

Systemboard.

48ThinkPadT420andT420iHardwareMaintenanceManual

Errormessages

Table3.Errormessages

Symptomorerror

Fanerror.1.Fan.

Thermalsensingerror.

Thissystemdoesnotsupportbatteriesthatarenot
genuineLenovo-madeorauthorized.Thissystemwill
continuetoboot,butmaynotchargeunauthorized
batteries.

Attention:Lenovohasnoresponsibilityforthe
performanceorsafetyofunauthorizedbatteries,and
providesnowarrantiesforfailuresordamagearisingout
oftheiruse.

FRUoraction,insequence

2.Thermalgrease.

3.Systemboard.

Systemboard.

Replacethebattery.

Chapter4.Relatedserviceinformation49

Beepsymptoms

Table4.Beepsymptoms

Symptomorerror

Onebeepandablank,unreadable,orashingLCD.1.ReseattheLCDconnector.

Onelongandtwoshortbeeps,andablankorunreadable
LCD.

Twoshortbeepswitherrorcodes.

Twoshortbeepsandablankscreen.

Twoormorebeeps,oracontinuousbeep.Operating
systemstartssuccessfully.

Threeshortbeeps,pause,threemoreshortbeeps,and
oneshortbeep.

Oneshortbeep,pause,threeshortbeeps,pause,three
moreshortbeeps,andoneshortbeep.

Onlythecursorappears.

Fourcyclesoffourshortbeepsandablankscreen.

Fiveshortbeepsandablankscreen.

FRUoraction,insequence

2.LCDassembly.

3.ExternalCRT .

4.Systemboard.

1.Systemboard.

2.LCDassembly.

3.DIMM.

POSTerror .See“Numericerrorcodes”onpage47.

1.Systemboard.

2.DIMM.

Ifamini-PCIEthernetcardisinstalled,conrmthatAlert
OnLAN2intheThinkPadSetupprogramisdisabled.

1.DIMM.

2.Systemboard.

Reinstalltheoperatingsystem.

Systemboard(securitychip)

Systemboard

No-beepsymptoms

Table5.No-beepsymptoms

Symptomorerror

Nobeep,power-onindicatoron,LCDblank,andno
POST.

Nobeep,power-onindicatoron,andLCDblankduring
POST.

Thepower-onpasswordpromptappears.Apower-onpasswordorasupervisorpasswordisset.

Thehard-diskpasswordpromptappears.Ahard-diskpasswordisset.Typethepasswordand

FRUoraction,insequence

1.Makesurethateveryconnectorisconnected
tightlyandcorrectly.

2.DIMM.

3.Systemboard.

1.ReseatDIMM.

2.Systemboard.

TypethepasswordandpressEnter.

pressEnter.

LCD-relatedsymptoms

Important:TheTFTLCDforthenotebookcomputercontainsmanythin-lmtransistors(TFTs).Thepresenceofa

smallnumberofdotsthataremissing,discolored,oralwayslightedischaracteristicofTFTLCDtechnology,but
excessivepixelproblemscancauseviewingconcerns.

IftheLCDyouareservicinghastwoorlessvisibledefectivepixels,itshouldnotbeconsideredfaulty.However,ifthe
LCDhasthreeormorevisibledefectivepixels,itwillbedeemedasdefectivebyLenovoanditshouldbereplaced.

Notes:

•ThispolicyappliestoallThinkPadNotebookspurchasedon1January,2008orlater.

50ThinkPadT420andT420iHardwareMaintenanceManual

•LenovowillnotprovidereplacementiftheLCDiswithinspecicationaswecannotguaranteethatany
replacementLCDwillhavezeropixeldefects.

•OnepixelconsistsofR,G,Bsub-pixels.

Table6.LCD-relatedsymptoms

Symptomorerror

Nobeep,power-onindicatoron,andablankLCDduring

FRUoraction,insequence

Systemboard.

POST.

•LCDbacklightnotworking.

•LCDtoodark.

•LCDbrightnesscannotbeadjusted.

1.ReseattheLCDconnectors.

2.LCDassembly.

3.Systemboard.

•LCDcontrastcannotbeadjusted.

•LCDscreenunreadable.

•Charactersmissingpixels.

•Screenabnormal.

•Wrongcolordisplayed.

1.Seeimportantnotefor“LCD-relatedsymptoms.”

2.ReseatallLCDconnectors.

3.LCDassembly.

4.Systemboard.

HorizontalorverticallinesdisplayedonLCD.LCDassembly.

Chapter4.Relatedserviceinformation51

Intermittentproblems

Intermittentsystemhangproblemscanbeduetoavarietyofcausesthathavenothingtodowithahardware
defect,suchascosmicradiation,electrostaticdischarge,orsoftwareerrors.FRUreplacementshouldbe
consideredonlywhenaproblemrecurs.

Whenanalyzinganintermittentproblem,dothefollowing:

1.Runthediagnostictestforthesystemboardinloopmodeatleast10times.

2.Ifnoerrorisdetected,donotreplaceanyFRUs.

3.Ifanyerrorisdetected,replacetheFRUshownbytheFRUcode.Rerunthetesttoverifythatno
moreerrorsexist.

Undeterminedproblems

Ifthediagnostictestsdidnotidentifytheadapterordevicethathasfailed,ifwrongdevicesareinstalled,
orifthesystemsimplyisnotoperating,followtheseprocedurestoisolatethefailingFRU(donotisolate
FRUsthathavenodefects).

Verifythatallattacheddevicesaresupportedbythecomputer.

Verifythatthepowersupplybeingusedatthetimeofthefailureisoperatingcorrectly.(See“Powersystem
checkout”onpage37.)

1.Turnoffthecomputer.

2.VisuallycheckeachFRUfordamage.ReplaceanydamagedFRU.

3.Removeordisconnectallofthefollowingdevices:
a.Non- ThinkPaddevices
b.Devicesattachedtothedockingstationortheportreplicator
c.Printer,mouse,andotherexternaldevices
d.Batterypack
e.Harddiskdrive
f.Externaldiskettedriveoropticaldrive
g.DIMM
h.Opticaldiskordisketteintheinternaldrive
i.PCCards

4.Turnonthecomputer.

5.Determinewhethertheproblemhasbeensolved.

6.Iftheproblemdoesnotrecur,reconnecttheremoveddevicesoneatatimeuntilyoundthefailingFRU.

7.Iftheproblemremains,replacethefollowingFRUsoneatatime(donotreplaceanondefectiveFRU):
a.Systemboard
b.LCDassembly

52ThinkPadT420andT420iHardwareMaintenanceManual

Chapter5.Statusindicators

7

1

2

6

8

9

3

4 5

Thischapterpresentsthesystemstatusindicatorsthatshowthestatusofthecomputer.

©CopyrightLenovo2012

53

5

6

11

1 0

Table7.Statusindicators

R

IndicatorMeaning

1

Speakermute

Orange:

Thespeakerisonmute.Tosetthespeakersonmuteorunmute,
pressthespeakermutebutton.

2

Microphonemute

Orange:

Themicrophoneisonmute.Noneoftherecordingdevicesis
availablewhilethemicrophonemuteisonbydefault.

3

WirelessLAN,WirelessWAN,
orWiMAXstatus

Green:

ThewirelessLANfeature(theIEEE802.11b/gstandard,802.11
a/b/g,or802.11n),wirelessWANfeature,orWiMaxfeatureis
on,andtheradiolinkisreadyforuse.

Dataisbeingtransmitted.

4

BluetoothwirelessorWireless
USBstatus

Green:

TheBluetoothwirelessfeatureison,andtheradiolinkisready
foruse.

Dataisbeingtransmitted.

5

Deviceaccess

Green:

Dataisbeingreadfromorwrittentotheharddiskdrive,the
diskettedrive,orthedriveintheSerialUltrabayEnhanced
device.Whenthisindicatorison,donotputthecomputerinto
sleep(standby)modeorturnoffthecomputer.

Note:Donotmovethesystemwhilethegreendeviceaccesslightison.
Suddenphysicalshockcouldcausedriveerrors.

54ThinkPadT420andT420iHardwareMaintenanceManual

Table7.Statusindicators(continued)

IndicatorMeaning

6

Poweron

7

Numericlock(On-screen
indicator)

8

SerialUltrabayEnhanced
devicestatus

Green:

Thecomputerisonandreadytouse.Thisindicatorstayslit
aroundthepower-onbuttonwheneverthecomputerisonand
isnotinsleep(standby)mode.

Note:Thisindicatorblinkswhenthecomputerisinsleepmode.

Bydefault,whenthenumericlockison,thenumericlockindicatoris
displayedonthescreen.

Green:

ASerialUltrabayEnhanceddeviceisinstalledandinuse.

Blinkinggreen:

ASerialUltrabayEnhanceddeviceisintheprocessofbeing
detached.

Turnoff:

ASerialUltrabayEnhanceddeviceisreadytobeattachedor
detached.

9

Capslock

Green:

CapsLockmodeisenabled.ToenableordisableCapsLock
mode,presstheCapsLockkey .

10

Batterystatus

Green:

Thebatterychargelevelis20%orhigher.

Orange:

Thebatterychargelevelisbetween5%and20%.

Fastblinkingorange:

Thebatterychargelevelislowerthan5%.

Slowblinkingorange:

Thebatteryisbeingcharged.Whenitreaches20%,theblinking
colorchangestogreen.

Slowblinkinggreen:

Thebatterychargelevelisbetween20%and80%,and
chargingiscontinuing.Whenthebatteryreaches80%charge,
thebatterystatusindicatorstopsblinking,butthechargingmay
continueuntilthebatteryis100%charged.
Note:Ifthecomputerisoperatingonbatterypower,thebattery
statusindicatordoesnotworkwhilethecomputeristurnedoff
orisinsleep(standby)modeorhibernationmode.

Quickblinkingorange:

Anerroroccurredinthebattery.

Thebatterystatusindicatorblinksthreetimes:

Chapter5.Statusindicators55

Table7.Statusindicators(continued)

IndicatorMeaning

Theacpoweradapterisattachedtothecomputer.

Thebatterystatusindicatorisoff:

Thebatterypackofthecomputerisfullychargedordetached.

11

Sleep(standbyforWindows
XP)status

Green:

Thecomputerisinsleep(standby)mode.

Blinkinggreen:

Thecomputerisenteringsleep(standby)modeorhibernation
mode,orisresumingnormaloperation.

56ThinkPadT420andT420iHardwareMaintenanceManual

Chapter6.Fnkeycombinations

ThefollowingtableshowsthefunctionofeachcombinationofFnwithafunctionkey.

Table8.Fnkeycombinations

KeycombinationDescription

Fn+F1Reserved.

Fn+F2Lockthecomputer.

Fn+F3

Fn+F4

Fn+F5

Fn+F6

Fn+F7Applyapresentationschemedirectly,withnoneedtostartPresentationDirector.

Selectapowerplan(inWindowsXP ,powerscheme)thathasbeencreatedbyPowerManager,
oradjustthepowerlevelbyusingtheslidercontrol.Whenyoupressthiscombination,a
panelforselectingapowerplan(powerscheme)appears.

Notes:

Tousethiscombinationofthekeys,ThinkPadPMdevicedrivermusthavebeeninstalled
onthecomputer.

IfyouhaveloggedonwithanadministratoruserIDinWindowsXP ,andyoupressFn+F3,
thepanelforselectingapowerschemeappears.Ifyouhaveloggedonwithanotheruser
IDinWindowsXP ,andyoupressFn+F3,thepaneldoesnotappear.

Putthecomputerinsleep(standby)mode.Toreturntonormaloperation,presstheFnkey
only,withoutpressingafunctionkey.

Notes:

Tousethiscombinationofthekeys,ThinkPadPMdevicedrivermusthavebeeninstalled
onthecomputer.

Ifyouwanttousethecombinationtoputthecomputerintohibernationmodeor
do-nothingmode(inWindowsXP ,shutthecomputerdownorshowthepanelforturning
offthecomputer),changethesettingsinthePowerManager.

Enableordisablethebuilt-inwirelessnetworkingfeatures.IfyoupressFn+F5,alistofwireless
featuresisdisplayed.Y oucanquicklychangethepowerstateofeachfeatureinthelist.
Notes:IfyouwanttouseFn+F5toenableordisablethewirelessfeatures,thefollowing
devicedriversmustbeinstalledonthecomputerbeforehand:

•PowerManagementdriver

•OnScreenDisplayUtility

•Wirelessdevicedrivers

Changethecameraandaudiosettings.WhenyoupressFn+F6,thecameraandaudiosetting
windowisopenedandthecamerapreviewisturnedon.
Note:Thecamerasettingsareaonlyappearsifthecomputerhasanintegratedcamera.

©CopyrightLenovo2012

TodisablethisfunctionandusetheFn+F7keycombinationforswitchingadisplayoutput
location,startPresentationDirector,andchangethesettings.

Note:IfthecomputerisanWindows7model,itdoesnotsupportpresentationschemes,
howevertheFn+F7combinationmightstillbeusedtoswitchdisplayoutputlocation.

ForWindows7:

Switchbetweenthecomputerdisplayandanexternalmonitor.Windowswillshowthese
displayoptions:

•Computerdisplayonly(LCD)

•Computerdisplayandexternalmonitor(sameimage)

•Computerdisplayandexternalmonitor(extendeddesktopfunction)

•Externalmonitoronly

57

Table8.Fnkeycombinations(continued)

KeycombinationDescription

Note:Toswitchbetweenthecomputerdisplayandanexternalmonitor,theWin+Pkey

combinationisalsoavailable.

ForWindowsVistaandWindowsXP:

Switchbetweenthecomputerdisplayandanexternalmonitor.Ifanexternalmonitoris
attached,computeroutputisdisplayedinthefollowingthreepatternsbyturns:

•Externalmonitor(CRTdisplay)

•Computerdisplayandexternalmonitor(LCD+CRTdisplay)

•Computerdisplay(LCD)

Notes:

Thisfunctionisnotsupportedifdifferentdesktopimagesaredisplayedonthecomputer
displayandtheexternalmonitor(theExtenddesktopfunction).

ThisfunctiondoesnotworkwhileaDVDmovieoravideoclipisplaying.

Toenablethisfunction,startPresentationDirector,andchangethesettings.

Note:MultipleuserscanlogontoasingleoperatingsystembyusingdifferentuserIDs.Each
userneedstodothefollowing:ClickStart➙AllPrograms➙ThinkVantage➙Presentation
Director,andchangetheFn+F7settings.

Fn+F8

ChangethesettingsoftheUltraNav

®

pointingdevice.

Fn+F9Reserved.

Fn+F10Reserved.

Fn+F11Reserved.

Fn+F12Putthecomputerintohibernationmode.T oreturntonormaloperation,pressthepower

buttonforlessthanfourseconds.

Notes:

Tousethiscombinationofthekeys,ThinkPadPMdevicedrivermusthavebeeninstalled
onthecomputer.

ThoughthescreenfadesoutimmediatelyafterFn+F12arepressed,thecomputer
doesnotenterthehibernationmodeimmediately.Donotmovethesystemuntilthe
sleep(standby)statusindicatorstopsblinking.Movingthecomputerwhenitisentering
hibernationmightcausecorruptionoftheharddiskdrive.

Fn+PgUp

TurntheThinkLight

®

onoroff.
Note:ThisfunctionissupportedonlyontheThinkPadNotebooksthathavetheThinkLight.
TheonoroffstatusoftheThinkLightisshownonthescreenforafewsecondswhenyou
pressFn+PgUp.

Fn+HomeThecomputerdisplaybecomesbrighter.

Thepurposeofthismethodistochangethebrightnessleveltemporarily.OnWindowsVista,
thedefaultbrightnesslevelisloadedaftersleep(standby),hibernation,reboot,ordetachingor
attachinganacpoweradapter.Tochangethedefaultbrightnesslevel,changethesettingsof
thePowerOptionintheControlPanelorusethePowerManager.

Fn+EndThecomputerdisplaybecomesdimmer.

Thepurposeofthismethodistochangethebrightnessleveltemporarily.OnWindowsVista,
thedefaultbrightnesslevelisloadedaftersleep(standby),hibernation,reboot,ordetachingor
attachinganacpoweradapter.Tochangethedefaultbrightnesslevel,changethesettingsof
thePowerOptionintheControlPanelorusethePowerManager.

Fn+SpacebarEnabletheFullScreenMagnierfunction.

58ThinkPadT420andT420iHardwareMaintenanceManual

Table8.Fnkeycombinations(continued)

KeycombinationDescription

Fn+PrtScHavethesamefunctionastheSysRqkey.

Fn+ScrLk

Enableordisablethenumerickeypad.Theindicatorofnumericlockwillbedisplayedon
thescreen.

Fn+Pause

Fn+cursorkeys

HavethesamefunctionastheBreakkey.

ThesekeycombinationsworkwithWindowsMediaPlayer.Theyhavethefollowingfunctions:

•Fn+downarrowkey:PlayorPause

•Fn+uparrowkey:Stop

•Fn+rightarrowkey:NextTrack

•Fn+leftarrowkey:PreviousT rack

Chapter6.Fnkeycombinations59

60ThinkPadT420andT420iHardwareMaintenanceManual

Chapter7.FRUreplacementnotices

Thischapterpresentsnoticesrelatedtoremovingandreplacingparts.Readthischaptercarefullybefore
replacinganyFRU.

ExternalCRUstatementtocustomers:

Someproblemswithyourproductcanberesolvedwithareplacementpartyoucaninstallyourself,called
a“CustomerReplaceableUnit”or“CRU.”SomeCRUsaredesignatedasSelf-serviceCRUsandothers
aredesignatedasOptional-serviceCRUs.InstallationofSelf-serviceCRUsisyourresponsibility;youmay

requestthatLenovoinstallsanOptional-serviceCRUaccordingtothewarrantyserviceforyourproduct.

WhereyouareinstallingtheCRU,LenovowillshiptheCRUtoyou.CRUinformationandreplacement
instructionsareshippedwithyourproductandareavailablefromLenovoatanytimeuponrequest.Y oumay
ndalistofCRUsinthepublicationsthatshipwithyourproductorathttp://www.lenovo.com/CRUs.You
mayberequiredtoreturnthedefectivepartthatisreplacedbytheCRU.Whenreturnisrequired:(1)return
instructions,aprepaidshippinglabel,andacontainerwillbeincludedwiththereplacementCRU;and(2)you
maybechargedforthereplacementCRUifLenovodoesnotreceivethedefectivepartwithinthirty(30)days
ofyourreceiptofthereplacementCRU.SeeyourLenovoLimitedWarrantydocumentationforfulldetails.

Screwnotices

Loosescrewscancauseareliabilityproblem.IntheThinkPadnotebookcomputer,thisproblemisaddressed
withspecialnylon-coatedscrewsthathavethefollowingcharacteristics:

•Theymaintaintightconnections.

•Theydonoteasilycomeloose,evenwithshockorvibration.

•Theyarehardertotighten.

Dothefollowingwhenyouservicethismachine:

•Keepthescrewkitinyourtoolbag.Forthepartnumberofthescrewkit,see“Miscellaneousparts”on
page162.

•Itisrecommendedtousenewscrews.

•Itisrecommendedtouseeachscrewonlyonce.

•Useatorquescrewdriverifyouhaveone.

Tightenscrewsasfollows:

•Plastictoplastic

Turnanadditional90degreesafterthescrewheadtouchesthesurfaceoftheplasticpart:

•Logiccardtoplastic

Turnanadditional180degreesafterthescrewheadtouchesthesurfaceofthelogiccard:

©CopyrightLenovo2012

61

•T orquedriver

Ifyouhaveatorquedriver,refertotheT orquecolumninthescrewinformationtableforeachstep.

•Makesurethatyouusethecorrectscrew.Itisrecommendedtousenewscrewsforreplacements.If
youhaveatorquescrewdriver,tightenallscrewsrmlytothetorquespeciedinthescrewinformation
tableforeachstep.

•Ensuretorquescrewdriversarecalibratedcorrectlyfollowingcountryspecications.

Retainingserialnumbers

Thissectionincludesthefollowingdescriptions:

•“Restoringtheserialnumberofthesystemunit”onpage62

•“RetainingtheUUID”onpage63

•“ReadingorwritingtheECAinformation”onpage63

Restoringtheserialnumberofthesystemunit

Whenthecomputerwasmanufactured,theEEPROMonthesystemboardwasloadedwiththeserial
numbersofthesystemandallmajorcomponents.Thesenumbersneedtoremainthesamethroughout
thelifeofthecomputer.

Ifyoureplacethesystemboard,youmustrestoretheserialnumberofthesystemunittoitsoriginalvalue.

Beforereplacingthesystemboard,savetheoriginalserialnumberbydoingthefollowing:

1.InstalltheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlater,andrestartthe
computer.

2.Fromthemainmenu,select1.SetSystemIdentication.

3.Select2.ReadS/NdatafromEEPROM.

Theserialnumberofeachdeviceinyourcomputerisdisplayed;theserialnumberofthesystemunitis
listedasfollows:

•20:Serialnumber

Writedownthatnumber.

Note:Theserialnumberofthesystemunitisalsowrittenonthelabelattachedtothebottomofthecomputer.

Afteryouhavereplacedthesystemboard,restoretheserialnumberbydoingthefollowing:

1.InstalltheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlaterandrestartthe
computer.

2.Fromthemainmenu,select1.SetSystemIdentication.

3.Select1.AddS/NdatafromEEPROM.Followtheinstructionsonthescreen.

IftheMTMandProductIDnumbersdifferfromeachotherontherearlabel,usewhatisshownforthe
ProductIDeld.Seeexamplebelow:

62ThinkPadT420andT420iHardwareMaintenanceManual

MTMonrearlabel:

TTTT-CTOS/NSSSSSSS

ProductIDonrearlabel:

Intheexample,theSerialNumbertobeinputis“1STTTTMMMSSSSSSS”.

TTTT-MMM(UsethisnumberwhensettingSerial
Number)

RetainingtheUUID

TheUniversallyUniqueIdentier(UUID)isa128-bitnumberuniquelyassignedtoyourcomputerat
productionandstoredintheEEPROMofyoursystemboard.Thealgorithmthatgeneratesthenumberis
designedtoprovideuniqueIDsuntiltheyearA.D.3400.Notwocomputersintheworldhavethesame
number.

Whenyoureplacethesystemboard,youmustsettheUUIDonthenewsystemboardasfollows:

1.InstalltheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlater,andrestartthe
computer.

2.Fromthemainmenu,select4.AssignUUID.AnewUUIDiscreatedandwritten.IfavalidUUIDalready
exists,itisnotoverwritten.

ReadingorwritingtheECAinformation

InformationonEngineeringChangeAnnouncements(ECA)arestoredintheEEPROMofthesystemboard.
TheelectronicstorageofthisinformationsimpliestheproceduretocheckiftheECAhasbeenpreviously
appliedtoamachine.ThemachinedoesnotneedtobedisassembledtocheckfortheECAapplication.

TocheckwhatECAshavebeenpreviouslyappliedtothemachine,usetheECAInformationRead/Write
functionontheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlater.

1.InserttheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlater,andrestartthe
computer.

2.Fromthemainmenu,select6.SetECAInformation.

3.ToreadECAinformation,select2.ReadECA/reworknumberfromEEPROMandfollowthe
instruction.

4.Toreadboxbuilddate,select5.ReadboxbuilddatefromEEPROM,andfollowtheinstructionon
thescreen.

AfteranECAhasbeenappliedtothemachine,theEEPROMmustbeupdatedtoreecttheECA's
application.UsetheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlatertoupdatethe
EEPROM.

Note:OnlytheECAnumberisstoredintheEEPROM.ThemachinetypeoftheECAisassumedbethesame
asthemachinetypeofthemachinethathadtheECAappliedtoit.

1.InserttheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlater,andrestartthe
computer.

2.Fromthemainmenu,select6.SetECAInformation.

3.TowriteECAinformation,select1.WriteECA/reworknumberfromEEPROM,andfollowthe
instruction.

4.Towriteboxbuilddate,select4.WriteboxbuilddatefromEEPROM,andfollowtheinstructionon
thescreen.

Ifthesystemboardisbeingreplaced,trytoreadtheECAinformationfromtheoldsystemboardandtransfer
theinformationtothenewsystem.Ifthesystemboardisinoperable,thiswillnotbepossible.

Chapter7.FRUreplacementnotices63

64ThinkPadT420andT420iHardwareMaintenanceManual

Chapter8.RemovingandreplacingaFRU

ThischapterpresentsdirectionsanddrawingsforuseinremovingandreplacingaFRU.

ExternalCRUstatementtocustomers:

Someproblemswithyourproductcanberesolvedwithareplacementpartyoucaninstallyourself,called
a“CustomerReplaceableUnit”or“CRU.”SomeCRUsaredesignatedasSelf-serviceCRUsandothers
aredesignatedasOptional-serviceCRUs.InstallationofSelf-serviceCRUsisyourresponsibility;youmay

requestthatLenovoinstallsanOptional-serviceCRUaccordingtothewarrantyserviceforyourproduct.

WhereyouareinstallingtheCRU,LenovowillshiptheCRUtoyou.CRUinformationandreplacement
instructionsareshippedwithyourproductandareavailablefromLenovoatanytimeuponrequest.Y oumay
ndalistofCRUsinthepublicationsthatshipwithyourproductorathttp://www.lenovo.com/CRUs.You
mayberequiredtoreturnthedefectivepartthatisreplacedbytheCRU.Whenreturnisrequired:(1)return
instructions,aprepaidshippinglabel,andacontainerwillbeincludedwiththereplacementCRU;and(2)you
maybechargedforthereplacementCRUifLenovodoesnotreceivethedefectivepartwithinthirty(30)days
ofyourreceiptofthereplacementCRU.SeeyourLenovoLimitedWarrantydocumentationforfulldetails.

Besuretoobservethefollowinggeneralrules:

1.Donottrytoserviceanycomputerunlessyouhavebeentrainedandcertied.Anuntrainedpersonruns
theriskofdamagingparts.

2.BeforereplacinganyFRU,reviewChapter7“FRUreplacementnotices”onpage61.

3.BeginbyremovinganyFRUsthathavetoberemovedbeforereplacingthefailingFRU.AnysuchFRUs
arelistedatthetopofeachFRUreplacementpage.Removethemintheorderinwhichtheyarelisted.

4.FollowthecorrectsequenceinthestepsforremovingaFRU,asgiveninthedrawingsbythenumbers
insquarecallouts.

5.WhenturningascrewtoreplaceaFRU,turnitinthedirectionasgivenbythearrowinthedrawing.

6.WhenremovingaFRU,moveitinthedirectionasgivenbythearrowinthedrawing.

7.ToputthenewFRUinplace,reversetheremovalprocedureandfollowanynotesthatpertainto
replacement.Forinformationaboutconnectingandarranginginternalcables,seeChapter9“Locations”
onpage129.

8.WhenreplacingaFRU,usethecorrectscrew(s)asshownintheprocedures.

DANGER

BeforeremovinganyFRU,turnoffthecomputer ,unplugallpowercordsfromelectricaloutlets,
removethebatterypack,andthendisconnectanyinterconnectingcables.

Attention:AfterreplacingaFRU,donotturnonthecomputeruntilyouhavemadesurethatallscrews,

springs,andothersmallpartsareinplaceandnonearelooseinsidethecomputer.Verifythisbyshaking
thecomputergentlyandlisteningforrattlingsounds.Metallicpartsormetalakescancauseelectrical
shortcircuits.

Attention:Thesystemboardissensitiveto,andcanbedamagedby,electrostaticdischarge.Before
touchingit,establishpersonalgroundingbytouchingagroundpointwithonehandorbyusingan
electrostaticdischarge(ESD)strap(P/N6405959).

©CopyrightLenovo2012

65

BeforeservicingThinkPadT420andT420i

1

2

SomemodelsoftheThinkPadT420andT420iyouareservicingmighthavetheSIMcardthatthecustomer
hasinstalled.

IfthecomputeryouareservicinghastheSIMcard,removeitbeforeyoustarttheservicing.

ToremovetheSIMcard,youneedtoremovethebatterypackrst.(See“1010Batterypack”onpage67.)

Afteryounishtheservicing,makesurethatyouinsertthecardbackintotheslotrmly.

66ThinkPadT420andT420iHardwareMaintenanceManual

1010Batterypack

3

21

Importantnoticeforreplacingabatterypack:

TheLenovoThinkVantageT oolboxandLenovoSolutionCenter(inWindows7)haveanautomaticbattery
diagnosticcomponentthatdeterminesifthebatterypackisdefective.AbatterypackFRUshouldnotbe
replacedunlessthisdiagnostictestshowsthatthebatteryisdefective.

Theonlyexceptiontothisisifthebatterypackisphysicallydamagedoracustomerisreportingapossible
safetyissue.

IfLenovoThinkVantageT oolboxisnotinstalledinthecomputer,thecustomershoulddownloadthisprogram
beforeanon-physicallydamagedbatterypackisreplaced.Notethatthereplacementofaphysically
damagedbatterypackisnotcoveredbythewarranty.

Removalstepsofbatterypack

DANGER

Useonlythebatteryspeciedinthepartslistforyourcomputer .Anyotherbatterycouldignite
orexplode.

Unlockthebatterylatch1.Holdingthebatterylatchintheunlockedposition2,removethebatterypackin
thedirectionshownbyarrow3.

Wheninstalling:Installthebatterypackintheslot.Makesurethatthebatterylatchisinthelockedposition.

Chapter8.RemovingandreplacingaFRU67

1020ExpressCardblankbezel

1

2

RemovalstepsofExpressCardblankbezel

WhenyoupresstheExpressCardblankbezel1,itpopsout2.

Wheninstalling:Makesurethatthebezeliscorrectlyorientedasshowninthefollowinggure.

68ThinkPadT420andT420iHardwareMaintenanceManual

1030SerialUltrabayEnhanceddeviceortravelbezel

3

2

1

Foraccess,removethisFRU:

•“1010Batterypack”onpage67

RemovalstepsofSerialUltrabayEnhanceddeviceortravelbezel

Holdingthebaylocklatchintheunlockedposition1,slidethebayejectlatchinthedirectionshownby
arrow2,andthenpullouttheSerialUltrabayEnhanceddeviceorthetravelbezelinthedirectionshownby
arrow3tocompletelyremoveit.

Chapter8.RemovingandreplacingaFRU69

1040Harddiskdrive(HDD)andsolidstatedrive(SSD)

4

2

1

Foraccess,removethisFRU:

•“1010Batterypack”onpage67

Attention:

•Donotdropthedriveorapplyanyphysicalshocktoit.Thedriveissensitivetophysicalshock.Improper
handlingcancausedamageandpermanentlossofdata.

•Beforeremovingthedrive,havetheusermakeabackupcopyofalltheinformationonitifpossible.

•Neverremovethedrivewhilethesystemisoperatingorisinsuspendmode.

Removalstepsofharddiskdriveandsolidstatedrive

Note:Loosenthescrew1,butdonotremoveit.

StepScrew(quantity)Color

1

70ThinkPadT420andT420iHardwareMaintenanceManual

Capturescrew(1)

Torque

Black0.181Nm

(1.85kgfcm)

4

3

ForHDDandHDDrubberrails(9.5mm):

4

4

4

4

4

4

ForHDDandHDDrubberrails(7.0mm):

ForSSDandspacers:

Chapter8.RemovingandreplacingaFRU71

Wheninstalling:MakesurethatSSDspacersorHDDrubberrailsareattachedrmly.

72ThinkPadT420andT420iHardwareMaintenanceManual

1050DIMMslotcover

2

Foraccess,removethisFRU:

•“1010Batterypack”onpage67

RemovalstepsofDIMMslotcover

Note:Loosenthescrew1,butdonotremoveit.

Chapter8.RemovingandreplacingaFRU73

1060DIMM(intheslotontheundersideofthecomputer)

1

1

2

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

Note:YourcomputerhastwoDIMMslots:oneunderthekeyboardandanotherontheundersideofthe
computer.IfyouinstallaDIMMinonlyoneofthetwoslots,installitintheslotlocatedunderthekeyboard.

RemovalstepsofDIMM(intheslotontheundersideofthecomputer)

Wheninstalling:InsertthenotchedendoftheDIMMintothesocket.PresstheDIMMrmly,andpivotit

untilitsnapsintoplace.Makesurethatitisrmlyxedintheslotanddoesnotmoveeasily.

74ThinkPadT420andT420iHardwareMaintenanceManual

1070PCIExpressMiniCardforwirelessWAN

1

1

2

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

RemovalstepsofPCIExpressMiniCardforwirelessWAN

Instep1,unplugthejacksbyusingtheremovaltoolantennaRFconnector(P/N:08K7159),orpickthe
connectorswithyourngersandgentlyunplugtheminthedirectionofthearrow.

StepScrew(quantity)Color

2

M2×3mm,wafer-head,nylon-coated(1)

Torque

Black0.181Nm

(1.85kgfcm)

Chapter8.RemovingandreplacingaFRU75

3

Note:PlugtheyellowcableintothejacklabeledMAIN,andthebluecableintothejacklabeledAUX
onthecard.

IfthecomputeryouareservicingisawirelessWAN-readymodelanddoesnothaveawirelessWANcard,
routetheantennacablesandsecurethemwithatapeasshowninthefollowinggure.

76ThinkPadT420andT420iHardwareMaintenanceManual

1080Keyboard

1

2

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

Removalstepsofkeyboard

StepScrew(quantity)Color

1

M2×10mm,wafer-head,nylon-coated(1)Silver

Torque

0.181Nm
(1.85kgfcm)

Pushdownthekeyboardalittleandslideittowardthearrow2todetachthefrontedgeofthekeyboard
fromtheframe.

Chapter8.RemovingandreplacingaFRU77

Liftthekeyboardalittleinthedirectionshownbyarrow3,andthendetachtheconnector4.

Installationstepsofkeyboard

Wheninstallingthekeyboard,dothefollowing:

1.Attachthekeyboardconnector.

78ThinkPadT420andT420iHardwareMaintenanceManual

2.Attachthekeyboardsothatthekeyboardedgesaareundertheframe.

3.Tomakesurethatthefrontedgeofthekeyboardishousedrmly,gentlypressthekeyswithyourpalms
andslightlyslidethekeyboardtowardyouuntilitsnapsintoposition.

Chapter8.RemovingandreplacingaFRU79

4.Makesurethatthefrontedgeofthekeyboardbisattachedrmly.

b

b

b

5.Securethekeyboardbytighteningthescrewsfromthebottomsideofthecomputer.

80ThinkPadT420andT420iHardwareMaintenanceManual

1090DIMM(intheslotunderthekeyboard)

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

•“1080Keyboard”onpage77

Note:YourcomputerhastwoDIMMslots:oneunderthekeyboardandanotherontheundersideofthe
computer.IfyouinstallaDIMMinonlyoneofthetwoslots,installitintheslotlocatedunderthekeyboard.

RemovalstepsofDIMM(intheslotunderthekeyboard)

Chapter8.RemovingandreplacingaFRU81

1

2

3

2

Wheninstalling:InsertthenotchedendoftheDIMMintothesocket.PresstheDIMMrmly,andpivotit
untilitsnapsintoplace.Makesurethatitisrmlyxedintheslotanddoesnotmoveeasily.

82ThinkPadT420andT420iHardwareMaintenanceManual

1100Backupbattery

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

•“1080Keyboard”onpage77

Removalstepsofbackupbattery

DANGER

Useonlythebatteryspeciedinthepartslistforyourcomputer .Anyotherbatterycouldignite
orexplode.

Cablerouting:Attachthebackupbatteryandroutethecableasshowninthegurebelowandmake

surethatthebatteryconnectorisattachedrmly.

Chapter8.RemovingandreplacingaFRU83

84ThinkPadT420andT420iHardwareMaintenanceManual

1110PCIExpressMiniCardforwirelessLAN

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

•“1080Keyboard”onpage77

RemovalstepsofPCIExpressMiniCardforwirelessLAN

Instep1,unplugthejacksbyusingtheremovaltoolantennaRFconnector(P/N:08K7159),orpickthe
connectorswithyourngersandgentlyunplugtheminthedirectionofthearrow.

Note:Somemodelsmighthaveonlytwoantennacables.

StepScrew(quantity)Color

2

M2×10mm,wafer-head,nylon-coated(1)Silver

Torque

0.181Nm
(1.85kgfcm)

Chapter8.RemovingandreplacingaFRU85

3

Wheninstalling:

•InmodelswithawirelessLANcardthathastwoantennaconnectors,plugthegraycableintothejack
markedMAINorM,andtheblackcableintothejackmarkedAUXorAonthecard.Ifthecomputer
youareservicinghasthreecables,putthewhitecableinthecableprotectiontubeandsecureitwitha
tapeasshowninthisgure.

•InmodelswithawirelessLANcardthathasthreeantennaconnectors,plugthegraycable(MAIN)into
thejackmarkedTR1,thewhitecable(third)intothejackmarkedROorTR3,andtheblackcable(AUX)
intothejackmarkedTR2onthecard.

.

86ThinkPadT420andT420iHardwareMaintenanceManual

1120Keyboardbezelassembly,FPCcable,andBluethoothdaughter

2

2

2

2

1

card

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1020ExpressCardblankbezel”onpage68

•“1050DIMMslotcover”onpage73

•“1080Keyboard”onpage77

Note:TheFPCcableisattachedontheundersideofthekeyboardbezelassembly.Insomemodels,the
Bluetoothdaughtercardisalsoattachedontheundersideofthekeyboardbezelassembly.Forthemodels
thatdonothaveaBluetoothdaughtercard,skipsteps8to10.

Removalstepsofkeyboardbezelassembly,FPCcable,andBluetoothdaughtercard

StepScrew(quantity)Color

1

2

M2×3mm,wafer-head,nylon-coated(1)

M2×15mm,wafer-head,nylon-coated(4)

Torque

Black0.181Nm

(1.85kgfcm)

Black0.181Nm

(1.85kgfcm)

Chapter8.RemovingandreplacingaFRU87

StepScrew(quantity)Color

3

4

M2×3mm,wafer-head,nylon-coated(1)

Shoulderscrew(2)Silver

Torque

Black0.181Nm

(1.85kgfcm)

0.181Nm
(1.85kgfcm)

88ThinkPadT420andT420iHardwareMaintenanceManual

7

6

Wheninstalling:Makesurethattheconnectorisattachedrmly.

Chapter8.RemovingandreplacingaFRU89

1 7

1 7

Wheninstalling:Makesurethattheconnectorsareattachedrmly.

1 8

1 9

StepScrew(quantity)Color

13

M2×3mm,wafer-head,nylon-coated(1)

90ThinkPadT420andT420iHardwareMaintenanceManual

Torque

Black0.181Nm

(1.85kgfcm)

2 0

Wheninstalling:Makesurethattheconnectorisattachedrmly.

Chapter8.RemovingandreplacingaFRU91

1130SmartCard

1

1

2

3

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

•“1080Keyboard”onpage77

•“1120Keyboardbezelassembly,FPCcable,andBluethoothdaughtercard”onpage87

RemovalstepsofSmartCard

StepScrew(quantity)Color

1

M2×3mm,wafer-head,nylon-coated(2)

Black0.181Nm

Torque

(1.85kgfcm)

92ThinkPadT420andT420iHardwareMaintenanceManual

Wheninstalling:Makesurethattheconnectorisattachedrmly.

1

1

2

RemovalstepsofSmartCarddummyspacer

SomemodelshaveaSmartCarddummyspacerasamiscellaneouspart.Forthosemodels,removethe
spacerasshown:

StepScrew(quantity)Color

1

M2×3mm,wafer-head,nylon-coated(2)

Black0.181Nm

Torque

(1.85kgfcm)

Chapter8.RemovingandreplacingaFRU93

1140Modemdaughtercard(MDC)

1

1

2

Foraccess,removetheseFRUsinorder:

•“1010Batterypack”onpage67

•“1050DIMMslotcover”onpage73

•“1080Keyboard”onpage77

•“1120Keyboardbezelassembly,FPCcable,andBluethoothdaughtercard”onpage87

Removalstepsofmodemdaughtercard(MDC)

StepScrew(quantity)Color

1

M2×3mm,wafer-head,nylon-coated(2)

Wheninstalling:Makesurethattheconnectorisattachedrmly.

94ThinkPadT420andT420iHardwareMaintenanceManual

Torque

Black0.181Nm

(1.85kgfcm)