f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test,
measuring, and diagnostic equipment used in precision measurement. Consists of comparisons of two
instruments, one of which is a certified standard of known accuracy, to detect and adjust any discrepancy in
the accuracy of the instrument being compared.
g. Remove/Install. To remove and install the same item when required to perform service or other
maintenance functions. Install may be the act of emplacing, seating, or fixing into position a spare, repair
part, or module (component or assembly) in a manner to allow the proper functioning of an equipment or
h. Paint. To prepare and spray color coats of paint so that the ammunition can be identified and
protected. The color indicating primary use is applied, preferably, to the entire exterior surface as the
background color of the item. Other markings are to be repainted as original so as to retain proper
i. Replace. To remove an unserviceable item and install a serviceable counterpart in its place. "Replace"
is authorized by the MAC and assigned maintenance level is shown as the 3d position code of the Source,
Maintenance and Recoverability (SMR) code.
j. 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.
The following definitions are applicable to the "repair"
Services. Inspect, test, service, adjust, align, calibrate, and/or
Fault location/troubleshooting. 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).
Disassembly/assembly. The step-by-step breakdown (taking apart)
of a spare/functional group coded item to the level of its least
component, that is assigned a SMR code for the level of
maintenance under consideration (i.e., identified as maintenance
Actions. Welding, grinding, riveting, straightening, facing,
machining, and/or resurfacing.
k. 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. Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul
does not normally return an item to like new condition.
l. 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 (e.g., hours/miles) considered in classifying Army equipment/components.
B-3. EXPLANATION OF COLUMNS IN THE MAC, SECTION II
a. Column (1)-Group Number. Column 1 lists FGC numbers, the purpose of which is to identify
maintenance significant components, assemblies, subassemblies, and modules with the Next Higher
b. Column (2)-Component/Assembly. Column 2 contains the item 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, refer to "Maintenance Functions: outlined above.)