Hardware Maintenance Manual

Notes:
•Ensurethatyouusethecorrectscrew.Itisrecommendedtousenewscrewsforreplacements.
•Ifyouhaveatorquescrewdriver,tightenallscrewsfirmlytothetorquespecifiedinthescrewinformation
tableforeachstep.
•Ensurethatthetorquescrewdriversarecalibratedcorrectlyfollowingthecountryspecifications.
Retainingserialnumbers
Thissectionincludesthefollowingdescriptions:
•“Restoringtheserialnumberofthesystemunit”onpage56
•“RetainingtheUUID”onpage57
•“ReadingorwritingtheECAinformation”onpage57
Restoringtheserialnumberofthesystemunit
Whenthecomputerwasmanufactured,theEEPROMonthesystemboardwasloadedwiththeserial
numbersofthesystemandallmajorcomponents.Thesenumbersneedtoremainthesamethroughout
thelifeofthecomputer.
Ifyoureplacethesystemboard,youmustrestoretheserialnumberofthesystemunittoitsoriginalvalue.
Beforereplacingthesystemboard,savetheoriginalserialnumberbydoingthefollowing:
1.InstallthelatestversionofLENOVOThinkPadHardwareMaintenanceDisketteorMaintenanceKey,and
restartthecomputer.
2.Fromthemainmenu,select1.SetSystemIdentification.
3.T urnoffthecomputer,andthenturnonthecomputeragain.
4.WhentheThinkPadlogoisdisplayed,pressEsc.
5.Select2.ReadS/NdatafromEEPROM.Theserialnumberofthesystemunitislistedas20:Serial
number.
6.Writedownthatnumber.
Note:Theserialnumberofthesystemunitalsoiswrittenonthelabelattachedtothebottomofthecomputer.
Afteryouhavereplacedthesystemboard,restoretheserialnumberbydoingthefollowing:
1.InstallthelatestversionofLENOVOThinkPadHardwareMaintenanceDisketteorMaintenanceKey,
andthenrestartthecomputer.
2.Fromthemainmenu,select1.SetSystemIdentification.
3.T urnoffthecomputer,andthenturnonthecomputeragain.
4.WhentheThinkPadlogoisdisplayed,pressEsc.
5.Select1.AddS/NdatafromEEPROM.Followtheinstructionsonthescreen.
IftheMTMandProductIDnumbersdifferfromeachotherontherearlabel,usewhatisshownforthe
ProductIDfield.Seeexamplebelow:
56HardwareMaintenanceManual