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 system.
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 third position code of the SMR code.
The application of maintenance services1, including fault, location/troubleshooting2,
removal/installation, and disassembly/assembly3 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) necessary to restore an item to a completely
serviceable/operational condition as required by maintenance standards in appropriate technical publications
(i.e., Depot Maintenance Work Requirements (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
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 equipments/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 noun names of components, assemblies,
subassemblies, and modules for which maintenance is authorized.
Services-inspect, test, service, adjust, align, calibrate, and/or replace.
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).
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 (that is, assigned an SMR
code) for the category of maintenance under consideration.
Actions-welding, grinding, riveting, straightening, facing, remachinery, and/or resurfacing.