▁The ▁problem ▁must ▁be ▁identified ▁and ▁the ▁fault y ▁part ▁identified . ▁ ▁Part s ▁Pro c ure ment . ▁ ▁Rep lacement ▁parts ▁needed ▁( if ▁any ) ▁must ▁be ▁obtained ▁ ▁System ▁Rep air . ▁ ▁F ault y ▁parts ▁must ▁be ▁replaced ▁or ▁rep a ired . ▁ ▁S CH ED U LED ▁D OW N TIME ▁ ▁Pre vent ive ▁Main ten ance . ▁ ▁Pre vent ive ▁maintenance ▁checks ▁are ▁often ▁intr us ive ▁and ▁require ▁the ▁system ▁to ▁be ▁down ▁( unless ▁pro gn ost ics ▁are ▁used ), ▁e . g ., ▁checking ▁oil ▁in ▁a ▁car ▁engine . ▁ ▁System ▁Up grade . ▁ ▁System ▁dow nt ime ▁is ▁usually ▁required ▁to ▁bring ▁new ▁features ▁to ▁the ▁system . ▁ ▁Cal ibration . ▁ ▁Many ▁forms ▁of ▁mechanical ▁or ▁electronic ▁equipment ▁require ▁periodic ▁intr us ive ▁cal ibration . ▁ ▁Other ▁administrative ▁actions ▁ ▁There ▁are ▁four ▁main ▁ways ▁of ▁reducing ▁M DT : ▁ ▁Design ▁the ▁system ▁to ▁fail ▁less ▁often . ▁ ▁A ▁more ▁reliable ▁system ▁that ▁doesn ' t ▁fail ▁often ▁reduces ▁the ▁Down ▁Time . ▁ ▁Make ▁the ▁system ▁rep ai rable . ▁If ▁an ▁item ▁is ▁rep ai rable , ▁it ▁will ▁be ▁used ▁for ▁a ▁longer ▁time , ▁and ▁the ▁user ▁will ▁become ▁more ▁familiar ▁with ▁its ▁operation . ▁This ▁will ▁decrease ▁the ▁M DT ▁because ▁the ▁user ▁will ▁be ▁able ▁to ▁detect ▁ab normal ▁operation ▁sooner , ▁and ▁the ▁system ▁will ▁be ▁rep a ired ▁before ▁the ▁problem