TM9-4120-400-14
i. Repair. The application of maintenance servicesl, including fault location/troubleshooting2,
removal/installation, 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), end item, or system.
j. Overhaul. That maintenance effort (service/actions) prescribed to restore an item to a completely
serviceable/ operational condition as prescribed 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 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 equipments/components.
B-3.
EXPLANATION OF COLUMNS IN THE MAC, SECTION Il.
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 Functions. 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 Level. 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 the maintenance function at the indicated level 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 allocation chart. The symbol designations for the various
maintenance categories are as follows.
C.............................................................................Operator or Crew
O......................................Unit
F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direct Support Maintenance
H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Support Maintenance
D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Depot Maintenance
e. Column 5. Tools and Equipment. Column 5 specifies, by code, those common tool sets (not individual
tools) and special tools, TMDE, and support equipment required to perform the designated function.
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
Disassemble/assemble - 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.
B-2
