B-2. Maintenance Functions (cont).
h. Replace. TO remove an unserviceable item and install a serviceable counterpart in its place. Replace is
authorized by the MAC and is shown as the 3rd position code of the SMR code.
i. Repair. The application of maintenance services, including fault location/troubleshooting, removal/
installation, and disassembly assembly procedures, and maintenance actions to identify troubles and restore
serviceability to an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly,
module (component or assembly), end item, or system.
serviceable/operational condition as required by maintenance standards in appropriate technical publications (i.e.,
DMWR). Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not
normally return an item to like new condition.
k. 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.
B-3. Explanation of Columns in the MAC, Section II
a. Column 1, Group Number. Column 1 lists functional group code numbers, the purpose of which is to
identify maintenance significant components, assemblies, subassemblies, and modules with the next higher
assembly. End item group number shall be 00.
b. Column 2. Component/Assembly. Column 2 contains the names of components, assemblies,
subassemblies, and modules for which maintenance is authorized.
c. Column 3. Maintenance Function. Column 3 lists the functions to be performed on the item listed in Column
2. (For detailed explanation of these functions, see paragraph B-2).
d. Column 4. Maintenance Category. Column 4 specifies, by the listing of work time figure in the appropriate
subcolumn(s), the category of maintenance authorized to perform that maintenance function at the indicated
category of maintenance. If the number or complexity of the tasks within the listed maintenance function vary at
different maintenance categories, appropriate work time figures will be shown for each category. The work time
figure represents the average time required to restore an item (assembly, subassembly, component, module, end
item, or system) to a serviceable condition under typical field operating conditions. This time includes preparation
time (including any necessary disassembly/assembly time), troubleshooting/fault location time, and quality
assurance/quality control time in addition to the time required to perform the specific tasks identified for the
maintenance functions authorized in the maintenance application chart. The symbol designations for the various
maintenance categories are as follows:
Operator or crew
O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Direct Support Maintenance
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
j. Overhaul. That maintenance effort (service/action) prescribed to restore an item to a completely