TM 5-5420-203-14
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.
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 services/actions necessary for the restoration of unserviceable
equipment to 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 a work time figure
in the appropriate subcolumn(s), the category of maintenance authorized to perform the function listed in
column 3. This figure represents the active time required 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), fault location/troubleshooting, 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 allocation chart. The symbol designations for the various maintenance categories are as
follows:
C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Operator or Crew
.
O . . . . . . . . . . . . . . . . . . . . . ...... . . . . . . . . . . . . . . Unit Maintenance
F . . . . . . . . .. . . . . . . . . . . . . . . . . . . . .Direct Support Maintenance
H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Support Maintenance
D . . . . . . . . . . . . . . . . . . . . . . . . .....Depot Maintenance
B-2
