TM 9-4120-378-14
i. Repair. The application of maintenance services1 including fault location/troubleshooting2, removal/instal-
lation, and disassembly/assembly3 procedures, and maintenance actions4 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), and item, or system.
j. Overhaul. That maintenance effort (service/action) prescribed to restore an item to a completely 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 service/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 material mainte-
nance 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 and 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.
b. Column 2Component/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.)
