TM 9-2330-227-14&P
B-2. MAINTENANCE FUNCTIONS - CONTINUED
h. Replace. To remove an unserviceable item and install a serviceable counterpart in its place.
Replace is authorized by the MAC and shown as the 3rd position code of the SMR code.
i. Repair. The application of maintenance services1, including fault location/troubleshooting2,
removal/installation, and disassembly/assembly 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), end item, or system.
j. Overhaul. That maintenance effort (service or action) prescribed to restore an item to
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 a like new condition, in accordance with original manufacturing standards. Rebuild is
the highest degree of material 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. (See paragraph B-2 for a detailed explanation of these functions.)
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 worktime figures will be
shown for each category. The work time figure represents the average time required to restore an
item (assembly, subassembly, components, module, end item, or system) to a serviceable
condition under typical field operating conditions. This time includes preparation time (including
any necessary disassembly/assembiy time), troubleshooting/fault location time, and quality
assurance/quality control time, in addition to the time required to perform the specific tasks
1
Services - inspect, test, service, adjust, aline, calibrate, and/or replace.
2
Fault locate/troubleshoot - the process of investigating and detecting the cause of equipment
malfunctioning; the act of isolating a fault within a system or unit under test (UUT).
3
Disassembiy/assembly - encompasses the step-by-step taking apart (or breakdown) of a
spare/functional group coded item to the level of its least componency identified as maintenance
significant (i.e., assigned an SMR code) for the category of maintenance under consideration.
4
Actions - welding, grinding, riveting, straightening, facing, remachinery, and/or resurfacing.