Install. The act of emplacing, seating or fixing into position an item, part or module (component or assembly) in
a manner to allow the proper functioning of the equipment.
Replace. To replace unserviceable items with serviceable like items.
Repair. Those maintenance operations necessary to restore an item to serviceable condition through correction
of material damage or a specific failure. Repair may be accomplished at every category of maintenance.
Overhaul. That maintenance effort (services/actions) necessary to restore an item to a completely
serviceable/operational condition as prescribed by maintenance standards (i.e., DMWR) in appropriate technical
publications. Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not
normally return an item to like new condition.
Rebuild. Consists of those services/actions necessary for the restoration of unserviceable equipment to a like
new condition in accordance with original manufacturing standards. Rebuild is the highest degree of materiel
maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age
measurements (hours/miles, etc.) considered in classifying Army equipment/components.
Symbols. The uppercase letter placed in the appropriate column indicates the lowest level at which that
particular maintenance function is to be performed.
D-3. COLUMN ENTRIES USED IN THE MAC.
Column 1, Group Number. The functional group is a numerical group set up on a functional basis. The
applicable functional grouping indexes (obtained from TB 750-93-1, Functional Grouping Codes) are listed on the MAC in
the appropriate numerical sequence. These indexes are normally set up in accordance with their function and proximity
to one another.
Column 2, Component/Assembly. Column 2 contains a brief description of the components of each functional
Column 3, Maintenance Functions. Column 3 lists the functions to be performed on the item listed in column 2,
and indicates the lowest maintenance category authorized to perform these functions, (For detailed explanation or these
functions, see para D-2). The symbol designations for the various maintenance categories are as follows:
C - Operator or crew
D - Organizational maintenance
F - Direct support maintenance
H - General support maintenance
D - Depot maintenance