•Torquedriver
Ifyouhaveatorquedriver,refertothe“Torque”columnforeachstep.
•Makesurethatyouusethecorrectscrew.Ifyouhaveatorquescrewdriver,tightenallscrewsrmlytothe
torqueshowninthetable.Neveruseascrewthatyouremoved.Useanewone.Makesurethatall
ofthescrewsaretightenedrmly.
•Ensuretorquescrewdriversarecalibratedcorrectlyfollowingcountryspecications.
Retainingserialnumbers
Thissectionincludesthefollowingdescriptions:
•“Restoringtheserialnumberofthesystemunit”onpage56
•“RetainingtheUUID”onpage57
•“ReadingorwritingtheECAinformation”onpage57
Restoringtheserialnumberofthesystemunit
Whenthecomputerwasmanufactured,theEEPROMonthesystemboardwasloadedwiththeserial
numbersofthesystemandallmajorcomponents.Thesenumbersneedtoremainthesamethroughout
thelifeofthecomputer.
Ifyoureplacethesyst emboard,youmustrestoretheserialnumberofthesystemunittoitsoriginalvalue.
Beforereplacingthesystemboard,savetheoriginalserialnumberbydoingthefollowing:
1.InstalltheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlater,andrestartthe
computer.
2.F romthemainmenu,select1.SetSystemIdentication.
3.Select2.ReadS/NdatafromEEPROM.
Theserialnumberofeachdeviceinyourcomputerisdisplayed;theserialnumberofthesystemunitis
listedasfollows:
•20:Serialnumber
Writedownthatnumber.
Note:Theserialnumberofthesystemunitisalsowrittenonthelabelattachedtothebottomofthecomputer.
Afteryouhavereplacedthesystemboard,restoretheserialnumberbydoingthefollowing:
1.InstalltheLENOVOThinkPadHardwareMaintenanceDisketteVersion1.76orlaterandrestartthe
computer.
2.F romthemainmenu,select1.SetSystemIdentication.
3.Select1.AddS/NdatafromEEPROM.Followtheinstructionsonthescreen.
IftheMTMandProductIDnumbersdifferfromeachotherontherearlabel,usewhatisshownforthe
ProductIDeld.Seee xamplebelow:
56ThinkPadX220TabletandX220iTabletHardwareMaintenanceManual