Manual

1210SystemboardandExpressCardslotassembly
Foraccess,removetheseFRUsinorder:
“1010Batterypack”onpage63
“1020ExpressCardblankbezel”onpage64
“1030SerialUltrabayEnhanceddeviceortravelbezel”onpage65
“1040Harddiskdrive(HDD)andsolidstatedrive(SSD)”onpage66
“1050DIMMslotcover”onpage69
“1070PCIExpressMiniCardforwirelessWAN”onpage71
“1080Keyboard”onpage73
“1110PCIExpressMiniCardforwirelessLAN”onpage81
“1120Keyboardbezelassembly,FPCcable,andBluethoothdaughtercard”onpage83
“1150Speakerassembly”onpage91
“1160LCDunit”onpage93
“1170Fanassembly”onpage97
“1180CPU”onpage101
“1190BasecoverassemblyandDC-inconnectorcable”onpage102
Importantnoticesforhandlingthesystemboard:
Whenhandlingthesystemboard,bearthefollowinginmind.
Thesystemboardhasanaccelerometer,whichcanbebrokenbyapplyingseveralthousandsofG-forces.
Note:Droppingasystemboardfromaheightofaslittleas6inchessothatitfallsatonahardbenchcansubject
theaccelerometertoasmuchas6,000G'sofshock.
Becarefulnottodropthesystemboardonabenchtopthathasahardsurface,suchasmetal,wood,orcomposite.
Ifasystemboardisdropped,youmusttestit,usingPC-DoctorforDOS,tomakesurethattheHDDActive
ProtectionSystemstillfunctions.
Note:IfthetestshowsthatHDDActiveProtectionSystemisnotfunctioning,besuretodocumentthedropina
rejectreport,andreplacethesystemboard.
Avoidroughhandlingofanykind.
Ateverypointintheprocess,besurenottodroporstackthesystemboard.
Ifyouputasystemboarddown,besuretoputitonlyonapaddedsurfacesuchasanESDmatoracorrugated
conductivesurface.
Afterreplacingthesystemboard,runPC-DoctorforDOStomakesurethatHDDActiveProtectionSystemstill
functions.Theprocedureisasfollows:
1.Placethecomputeronahorizontalsurface.
2.RunDiagnosticsThinkPadDevicesHDDActiveProtectionT est.
Attention:Donotapplyphysicalshocktothecomputerwhilethetestisrunning.
RemovalstepsofsystemboardandExpressCardslotassembly
Thefollowingcomponentssolderedonthetopsideofthesystemboardareextremelysensitive.Whenyou
servicethesystemboard,avoidanykindofroughhandling.
a
CPU
b
AccelerometerchipfortheHDDActiveProtectionSystem
108ThinkPadT420andT420iHardwareMaintenanceManual