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 3rd position code of the SMR code.
i. Repair. The application of maintenance services1 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), and 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 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 equipment and components.
E-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.
b. Column 2-Component/Assembly. Column 2 contains the names of components, assemblies, subassemblies,
and modules for which maintenance is authorized.
Service-lnspect, test, service, adjust, aline, calibrate, and/or replace.
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 as SMR code for the level of maintenance under consideration (i.e., identification as
Actions-Welding, grinding, riveting, straightening, facing, machining, and/or resurfacing.